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Synthesis of Graphene Oxide Coating with Hydrophilic Polymers as Paclitaxel Anticancer Drug Delivery Systems
, M.Sc. Thesis Sharif University of Technology ; Adeli, Mohsen (Supervisor) ; Poujavadi, Ali (Co-Advisor)
Abstract
Nowadays, there is no perfect drug delivery for cancer therapy; also the healthy tissues can be damaged more than tumor tissues. To resolve this problem, the new drug delivery system based on nanostructured materials is useful. Graphene oxide (GO) is one of the most important graphene derivatives and a potential candidate for drug delivery system. It has high specific surface area so that it can load and deliver the drug in a good manner. Hydrophobicity of graphene restricts its application in nanomedicine. In order to improve its solubility in water, graphene should be modified by hydrophilic polymers. Therefore, in this study, in order to activate the graphene surface and increase its...
Electrochemical Determination of Piroxicam at thin Carbon
Nanoparticle Composite And Investigation of the Electrochemical Behavior and Synthesis of Catechols in the Presence of Mercapto Methyl Tetrazol as a Nucleophile
,
M.Sc. Thesis
Sharif University of Technology
;
Shahrokhian, Saeed
(Supervisor)
Abstract
The electrochemical oxidation behavior of the anti-inflammatory drug piroxicam was investigated. A carbon nanoparticle (CNP)-chitosan (CS) film-coated graphite electrode (PGE) was fabricated and the electrochemical behaviors of piroxicam on its surface was investigated by the means of cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). In comparison to the bare PGE, at the surface of the CNP-CS film modified electrode, the oxidation peak current of piroxicam increased significantly and the peak potential shifted negatively. Consequently, a simple and sensitive electroanalytical method was developed for the determination of piroxicam. The...
A Survey on Passing Sight Distance on Two-lane highways According to Road Conditions and Drivers' Behavior in Iran
,
M.Sc. Thesis
Sharif University of Technology
;
Vaziri, Manouchehr
(Supervisor)
Abstract
The main factor ensuring safety of passing maneuvers on two lane highways is known as Passing Sight Distance (PSD). The criteria presented in Iran's code and AASHTO Green book are provided by the results of researches conducted between years 1938 & 1941 in the United States. This research intends to find out whether some changes should be applied to the PSD criteria according to current vehicles' performance and driving behavior in Iran. For this purpose, about 8 hours of video films has been recorded from 3 different sites chosen from two-lane highways in Iran, resulted in 326 passing records. In the case of passing of two passenger cars The models provided by analyzing the videos show that...
Investigation on Hydrodynamic Locomotion of Sea Turtle
,
M.Sc. Thesis
Sharif University of Technology
;
Abbaspour, Madjid
(Supervisor)
Abstract
Nowadays, underwater vehicles designed by getting inspiration from aquatic animals’ motions have considerable merits; therefore, the issue of designing and building such vehicles has great significance. One of the aquatic animals, which can be a source of inspiration for designing vehicles with optimized propulsion and maneuver ability, is turtle. In order to design a robot under the inspiration of turtle locomotion, at first, it requires analyzing its locomotion carefully. In this project, it has been tried to do so. Having examined the motions of turtles and other aquatic animals thoroughly, the basics of their motions are achieved. Next, the locomotion of both sea and pond turtle are...
Digital multiplierless realization of a calcium-based plasticity model
, Article IEEE Transactions on Circuits and Systems II: Express Briefs ; Volume 64, Issue 7 , 2017 , Pages 832-836 ; 15497747 (ISSN) ; Soleimani, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
Calcium is a highly widespread and versatile intracellular ion that can control a wide range of temporal dynamics in the brain such as synaptic plasticity. This brief presents a novel and efficient digital circuit for implementing a calcium-based plasticity model aimed at reproducing relevant biological dynamics. Accordingly, we investigate the feasibility of the proposed model in a minimal neural network stressing on the effect of calcium oscillations on synaptic plasticity with various neuronal stimulation protocols. MATLAB simulations and physical implementations on field-programmable gate array confirm that the proposed model, with considerably low hardware overhead, can fairly mimic the...
The best approximation of some rational functions in uniform norm
, Article Applied Numerical Mathematics ; Volume 55, Issue 2 , 2005 , Pages 204-214 ; 01689274 (ISSN) ; Mehri, B ; Sharif University of Technology
2005
Abstract
Here we are concerned with the best approximation by polynomials to rational functions in the uniform norm. We give some new theorems about the best approximation of 1/(1+x) and 1/(x-a) where a>1. Finally we extend this problem to that of computing the best approximation of the Chebyshev expansion in uniform norm and give some results and conjectures about this. © 2005 IMACS. Published by Elsevier B.V. All rights reserved
Design and Implementation of Control Algorithm to Carry a load By Segway Robot
, M.Sc. Thesis Sharif University of Technology ; Bagheri Shouraki, Saeed (Supervisor)
Abstract
Recently, many investigations have been devoted to problems of controlling mobile-wheeled inverted pendulum (MWIP) models, which have been widely applied in the field of autonomous robotics and intelligent vehicles. The MWIP models are not only of theoretical interest but are also of practical interest. Many practical systems have been implemented that were based on the MWIP models, such as the JOE, the Segway, etc. Among these applications, the Segway PT has been a popular personal transporter, since it was invented in 2002 Such systems are characterized by the ability to balance on its two wheels and spin on the spot. This additional maneuverability allows them to easily navigate on...
Hub location problem considering an elastic demand
, Article CIE 2014 - 44th International Conference on Computers and Industrial Engineering and IMSS 2014 - 9th International Symposium on Intelligent Manufacturing and Service Systems, Joint International Symposium on "The Social Impacts of Developments in Information, Manufacturing and Service Systems" - Proceedings ; 2014 , pp. 581-588 ; Akbari Jokar, M. R ; Sharif University of Technology
2014
Abstract
In most hub location problem in the literature, the demand is independent of the market share. However, especially about the services and products which are not essential, this assumption does not mirror the reality. Considering the elastic demand increases the complexity and solution of the problem. The elasticity of demand depends on the utility of available hub. For simplicity, we assume that the utility of hub nodes are additive. Utility of the nodes is based on the attraction of the facility on that node and also the decay function of distance. In this paper we propose a new model for hub location problem in an airline industry with elastic demand. In this problem, passengers use hubs...
Albumin-graphene oxide conjugates; Carriers for anticancer drugs
, Article RSC Advances ; Vol. 4, issue. 62 , July , 2014 , pp. 33001-33006 ; ISSN: 20462069 ; Pourjavadi, A ; Adeli, M ; Sharif University of Technology
2014
Abstract
In order to improve its biological properties, graphene oxide can be modified with hydrophilic polymers. Therefore, in this study, the surface of graphene oxide was modified with polyethylene glycol and albumin by covalent methods. In the subsequent step, paclitaxel which is a hydrophobic anticancer drug was loaded onto the surface of the functionalized graphene by π-π interactions. The synthesis of the nanocarrier and its interaction with paclitaxel were evaluated by FT-IR, CD, TEM, UV, AFM, DLS and fluorescence experiments. Release of the loaded drug from albumin-graphene conjugate was investigated at pH 5.4, 6.8 and 7.4
A hybrid imperialist competitive-simulated annealing algorithm for a multisource multi-product location-routing-inventory problem
, Article Computers and Industrial Engineering ; Volume 101 , 2016 , Pages 116-127 ; 03608352 (ISSN) ; Akbari jokar, M. R ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
This article studies a multi-product and multi-period location-routing-inventory problem in which location-allocation, inventory and routing decisions are to be taken in a three-level supply chain including suppliers, depots and customers. Products are distributed from depots to customers by a homogeneous fleet of vehicles. Backlogging is allowable on condition that the backlog quantity of each customer does not exceed a predefined fraction of his demand. A mixed-integer programming formulation is presented to describe the problem then a new hybrid heuristic algorithm based on the simulated annealing and imperialist competitive algorithm is designed to solve the model. Comprehensive...
An efficient multiple-stage mathematical programming method for advanced single and multi-floor facility layout problems
, Article Applied Mathematical Modelling ; Volume 40, Issue 9-10 , 2016 , Pages 5605-5620 ; 0307904X (ISSN) ; Akbari Jokar, M. R ; Sharif University of Technology
Elsevier Inc
2016
Abstract
Single floor facility layout problem (FLP) is related to finding the arrangement of a given number of departments within a facility; while in multi-floor FLP, the departments should be imbedded in some floors inside the facility. The significant influence of layout design on the effectiveness of any organization has turned FLP into an important issue. This paper presents a three- (two-) stage mathematical programming method to find competitive solutions for multi- (single-) floor problems. At the first stage, the departments are assigned to the floors through a mixed integer programming model (the single floor version does not require this stage). At the second stage, a nonlinear programming...
Simulation Study of Inflow Control Device
, M.Sc. Thesis Sharif University of Technology ; Shad, Saeed (Supervisor)
Abstract
Optimizing and improving the design of wells will have significant impact on any recovery method. As for horizontal wells, despite the fact that horizontal wells improve reservoir access, they suffer from significant pressure loss as well as limited flow control locations and flow control and management. In addition, reservoir quality varies along the length of the well and in the reservoir. This will add further complexity and challenge in well control and production optimization. The design of completions plays a significant role in improving the productivity of a well as well as the life of the reservoir. Intelligent or smart completions can be used to monitor, evaluate and manage the...
Facility and hub location model based on gravity rule
, Article Computers and Industrial Engineering ; Volume 109 , 2017 , Pages 28-38 ; 03608352 (ISSN) ; Akbari Jokar, M. R ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
This paper presents a model for “Domestic Facility and Hub Location” in transportation network. Number of hubs and facilities are unknown and the objective is to minimize the transportation cost, lost demand penalty and facility set up costs. Also the distribution of demand among domestic facilities and hubs adheres to gravity rule. To solve the problem, sequential and integrated approaches were undertaken. In the sequential approach, domestic facilities were allocated and hubs were selected afterwards. However the integrated approach deals with both concurrently, with a more sophisticated steps reaching to the solution. This is mainly because the demand itself is highly dependent to where...
Many to many hub and spoke location routing problem based on the gravity rule
, Article Uncertain Supply Chain Management ; Volume 6, Issue 4 , 2018 , Pages 393-406 ; 22916822 (ISSN) ; Akbari Jokar, M. R ; Sharif University of Technology
Growing Science
2018
Abstract
This paper examines the spoke and hub location decisions in a routing problem. To minimize the total cost, the study analyzes on how to locate the spokes, hubs and the allocation of spoke nodes to hub nodes, the routing among the nodes and the number of vehicles assigned to each hub thoroughly. As there might be no facility assigned to some points, unsatisfied demands must be distributed to other nodes with available facilities. Furthermore, the realized demand is determined by considering the perceived utility of each path, using The Gravity rule. For this purpose, the proposed nonlinear model is transformed into a linear programming model, where some tightening rules and preprocessing...
On the existence of proper stochastic Markov models for statistical reconstruction and prediction of chaotic time series
, Article Chaos, Solitons and Fractals ; Volume 123 , 2019 , Pages 373-382 ; 09600779 (ISSN) ; Salarieh, H ; Alasty, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this paper, the problem of statistical reconstruction and prediction of chaotic systems with unknown governing equations using stochastic Markov models is investigated. Using the time series of only one measurable state, an algorithm is proposed to design any orders of Markov models and the approach is state transition matrix extraction. Using this modeling, two goals are followed: first, using the time series, statistical reconstruction is performed through which the probability density and conditional probability density functions are reconstructed; and second, prediction is performed. For this problem, some estimators are required and here the maximum likelihood and the conditional...
A novel nonlinear function evaluation approach for efficient fpga mapping of neuron and synaptic plasticity models
, Article IEEE Transactions on Biomedical Circuits and Systems ; Volume 13, Issue 2 , 2019 , Pages 454-469 ; 19324545 (ISSN) ; Abolfathi, H ; Ahmadi, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Efficient hardware realization of spiking neural networks is of great significance in a wide variety of applications, such as high-speed modeling and simulation of large-scale neural systems. Exploiting the key features of FPGAS, this paper presents a novel nonlinear function evaluation approach, based on an effective uniform piecewise linear segmentation method, to efficiently approximate the nonlinear terms of neuron and synaptic plasticity models targeting low-cost digital implementation. The proposed approach takes advantage of a high-speed and extremely simple segment address encoder unit regardless of the number of segments, and therefore is capable of accurately approximating a given...
Cost evaluation of a two-echelon inventory system with lost sales and approximately normal demand
, Article Scientia Iranica ; Volume 13, Issue 1 , 2006 , Pages 105-112 ; 10263098 (ISSN) ; Seifbarghy, M ; Sharif University of Technology
Sharif University of Technology
2006
Abstract
The inventory system under consideration consists of one central warehouse and an arbitrary number of retailers controlled by a continuous review inventory policy (R,Q). Independent Poisson demands are assumed with constant transportation times for all retailers and a constant lead time for replenishing orders from an external supplier for the warehouse. Unsatisfied demands are assumed to be lost in the retailers and unsatisfied retailer orders are backordered in the warehouse. An approximate cost function is developed to find optimal reorder points for given batch sizes in all installations and the related accuracy is assessed through simulation. © Sharif University of Technology, January...
Cost evaluation of a two-echelon inventory system with lost sales and approximately Poisson demand
, Article International Journal of Production Economics ; Volume 102, Issue 2 , 2006 , Pages 244-254 ; 09255273 (ISSN) ; Akbari Jokar, M. R ; Sharif University of Technology
2006
Abstract
The inventory system under consideration consists of one central warehouse and many identical retailers controlled by continuous review inventory policy ( R, Q). We assume independent Poisson demands with constant transportation times for the retailers and a constant lead time for replenishing orders from an external supplier for the warehouse. Unsatisfied demands are assumed to be lost in the retailers and unsatisfied retailer orders are backordered in the warehouse. We develop an approximate cost function to find optimal reorder points for given batch sizes in all installations and the related accuracy is assessed through simulation. © 2005 Elsevier B.V. All rights reserved
Developing a model for a two-echelon two-item inventory system with lost sale and demand substitution
, Article 2006 IEEE International Conference on Management of Innovation and Technology, ICMIT 2006, Singapore, 21 June 2006 through 23 June 2006 ; Volume 2 , 2006 , Pages 926-930 ; 1424401488 (ISBN); 9781424401482 (ISBN) ; Zangeneh, S ; Sharif University of Technology
2006
Abstract
Almost all multi-echelon inventory models assume that demands which are not satisfied immediately can be backordered. In some situations, this assumption may not be realistic. For example, we can model stockouts as lost sales when the retailers are in a competitive market and customers can easily turn to another retailer for purchasing goods. So, in this study, assuming lost sales at the retailers, we consider a one-warehouse, several retailers, two-item inventory system where the items can be interchangeably used. Using the well-known METRIC-approximation as a framework, we present a heuristic for finding cost effective base-stock policies. In a numerical study with simulation, we find that...
Functionalized mesoporous silica-coated magnetic graphene oxide by polyglycerol-g-polycaprolactone with pH-responsive behavior: designed for targeted and controlled doxorubicin delivery
, Article Journal of Industrial and Engineering Chemistry ; 2015 ; ISSN: 1226086X ; Tehrani, Z. M ; Jokar, S ; Sharif University of Technology
2015
Abstract
In the present work a novel multifunctional drug nanocarrier was prepared. Polyglycerol-. g-polycaprolactone was grafted on Mesoporous silica-coated magnetic graphene oxide. Doxorubicin, as anticancer drug, was loaded on this carrier. The in vitro drug release showed the controlled pH responsive behavior. At the endosomal pH (pH 5.5) the amount of drug release enhanced. This nanocarrier would have potential application in the tumor therapy owing to its biodegradability, controlled release and pH responsive behavior