A Method for Performance Evaluation of Project Based on Combining the Concept of Golden Triangle and Decision Making Techniques

, M.Sc. Thesis Sharif University of Technology Shekari, Mohammad (Author) ; Mostafavi, Mostafa (Supervisor)

Abstract

In today’s highly competitive world, the countries with strong economies are able to produce their products at a lower price, better quality and at the right time in the market, therefore, in the performance evaluation of economic of the organizations and project management, several factors are involved; the most important are: time, price, and product quality. In this dissertation, a new method for performance evaluation in the field of project management based on combining the concept of the golden triangle of the project and the techniques available in decision science is presented. At first, three major areas of the golden triangle namely time, cost, and quality are selected for...

High-performance thin-film nanocomposite (TFN) forward osmosis (FO) membranes incorporated with porous hydrophobic-core/hydrophilic-shell nanoparticles

, Article Desalination ; Volume 515 , 2021 ; 00119164 (ISSN) Bagherzadeh, M ; Bayrami, A ; Shekari, Z ; Amini, M ; Sharif University of Technology

Elsevier B.V 2021

Abstract

The current article discusses some unprecedented information about the improvement in forward osmosis (FO) performance of polyethersulfone/polyamide (PES/PA) membranes, mainly focused on water flux and selectivity along with resistance to fouling phenomenon; which itself is brought in by the introduction of pre-modified zeolitic imidazolate framework-8 MOF nanoparticles. An investigation has been conducted on ZIF-8 nanoparticles surface with hydrophilicity feature to evaluate their potential for utilization in active polyamide layer of FO membranes for the first time, free from any decrease in water flux value (when hydrophobic ZIF-8 is exploited solely) and selectivity (when mSiO2 with...

A novel multigeneration system driven by a hybrid biogas-geothermal heat source, Part I: Thermodynamic modeling

, Article Energy Conversion and Management ; Volume 177 , 2018 , Pages 535-562 ; 01968904 (ISSN) Rostamzadeh, H ; Ghavami Gargari, S ; Shekari Namin, A ; Ghaebi, H ; Sharif University of Technology

Elsevier Ltd 2018

Abstract

Hybrid renewable energy heat sources provide more sustainable energy resources with high maintenance for high-efficient power plants. Multigeneration systems driven by a hybrid renewable source are proved as cutting-edge technologies in recent studies. In this study, a novel multigeneration system driven by a hybrid biogas-geothermal heat source is proposed and simulated. To demonstrate the feasibility of the proposed multigeneration system, first and second laws analysis are employed as the most effective tools for performance assessment of the systems. It is found that the proposed multigeneration system can produce overall heating capacity, overall cooling capacity, net output power,...

A novel multigeneration system driven by a hybrid biogas-geothermal heat source, Part II: Multi-criteria optimization

, Article Energy Conversion and Management ; Volume 180 , 2019 , Pages 859-888 ; 01968904 (ISSN) Rostamzadeh, H ; Gargari, S. G ; Shekari Namin, A ; Ghaebi, H ; Sharif University of Technology

Elsevier Ltd 2019

Abstract

Hybridization of biogas and geothermal energies for power plants can present a promising way to resolve drawbacks of each individual heat source from economic viewpoint, especially when low-temperature geothermal heat source is posited. Concerning this aspect of hybrid renewable heat sources, a novel hybrid biogas-geothermal multigeneration system was proposed in the first part of our study, which was modeled under privilege of thermodynamic laws. In continuation of our previous study, the current study is performed to investigate economic, environmental, and enviroeconomical aspects of the introduced system. Furthermore, single and multi-criteria optimizations of this integrated system are...

Critical Barriers to Successful Strategy Implementation: A Case Study of a Software Producing Firm

, M.Sc. Thesis Sharif University of Technology Shekari, Saeed (Author) ; Arati, Mohammad Reza (Supervisor) ; Alavi, Babak (Supervisor)

Abstract

This thesis seeks to identify the critical barriers to strategy implementation in an Iranian firm, and also concentrates on the readiness for strategy implementation phase. Previous studies show that many of strategic plans fail in implementation phase. Therefore, implementation and readiness for implementation phases are both important phases. The very few studies in this topic in Iranian industrial context illustrate the same issue in local context; however, these barriers may vary from one context to another. Different approaches and frameworks in the literature have been reviewed in order to build a theoretical frame work to seek the barriers to implementing a strategic plan in an...

Performance of three-level spectrally encoded spreadtime CDMA in the presence of multiple interferences [electronic resource]

, Article IET Communications ; July 2011, Volume 5, Issue 10, P. 1328-1335 Mashhadi, S. (Saeed) ; Mashhadi, Saeed ; Salehi, J. A ; Sharif University of Technology

Abstract

In this study the authors present an in-depth study, analysis and discussion on maximum likelihood (ML)-based receiver for a typical spectrally encoded spread-time CDMA in the presence of multiple narrowband interference (NBI) signals in an additive white Gaussian noise channel. Furthermore, the authors demonstrate that by combining useful properties of ML-based receiver and three-level codes, that is, codes with values of -1, 0, +1, the authors can introduce a new strategy in which superior performance with respect to previous receiver structure based on two-level codes, that is, codes with values of -1, +1, can be attained. With the help of an example, the authors drive, first, the...

An Fe3O4@SiO2@polypyrrole magnetic nanocomposite for the extraction and preconcentration of Cd(ii) and Ni(ii)

, Article Analytical Methods ; Volume 7, Issue 1 , Nov , 2015 , Pages 313-320 ; 17599660 (ISSN) Abolhasani, J ; Hosseinzadeh Khanmiri, R ; Ghorbani Kalhor, E ; Hassanpour, A ; Asgharinezhad, A. A ; Shekari, N ; Fathi, A ; Sharif University of Technology

Royal Society of Chemistry 2015

Abstract

This work describes a novel Fe3O4@SiO2@polypyrrole magnetic nanocomposite and its application in the preconcentration of Cd(ii) and Ni(ii) ions. The parameters affecting the preconcentration procedure were optimised by a Box-Behnken design using response surface methodology. Three variables (extraction time, magnetic sorbent amount, and pH) were selected as the main factors affecting the sorption step, while four variables (type, volume and concentration of the eluent, and elution time) were selected as the main factors in the optimisation study of the elution step. Following the sorption and elution of analytes, the ions were quantified by FAAS. The limits of detection were 0.3 and 1.2 ng...

Investigation of Multiphase Flow in Oil Wells (with Focus on Two Phase Flow), Flow Pattern Recognition and Modeling

, M.Sc. Thesis Sharif University of Technology Shams, Reza (Author) ; Shad, Saeed (Supervisor) ; Jamshidi, Saeed (Supervisor)

Abstract

The concurrent flow of oil and water is a common occurrence in the field of multiphase flow in different fields including petroleum industry. In oil and gas, production engineers often face a situation in which more than one phase is flowing through the producers. In such conditions an accurate assessment of pressure loss inside the well plays a vital role in efficient and effective production planning. Changes in well orientation, wellbore diameter, reservoir and fluid properties as well as fluid flow rates are among parameters in which will affect the flow patterns that can occur inside a well during its life time. These flow patterns are created as a result of a competition between...

Casing Design Optimization Considering Drilling and Production Conditions

, M.Sc. Thesis Sharif University of Technology Sadeghi, Mahdi (Author) ; Jamshidi, Saeed (Supervisor) ; Shad, Saeed (Supervisor)

Abstract

Casing design is one of the most expensive parts in the drilling of oil wells, and any cost reduction with the basic design of these casing strings will significantly reduce the total cost of the operation. In recent years, occurring scenarios-based casing design has become popular; Because in many cases, it eliminates non-occurring scenarios such as gas kick and saves on drilling costs. In this study, we have tried to investigate all scenarios that may occur during the lifetime of the well, whether drilling or production, and for each well, based on its own field information, possible scenarios for each casing part are selected separately and the applying loads are calculated. For this...

PRI (Palm Rotation Indicator): a metric for postural stability in dynamic nonprehensile manipulation [electronic resource]

, Article Journal of MECHANIKA ; 2012, Vol. 18, No. 4, pp. 461-466 Beigzadeh, B. (Borhan) ; Meghdar, Ali ; Sohrabpour, Saeed ; Sharif University of Technology

Abstract

In this study, we discuss the postural stability of a nonprehensile manipulation problem, which deals with multibody objects. As a metric for postural stability, we define PRI. Then, the system is posturally stable, if PRI is inside the convex hull of the object-manipulator contact surface. We then discuss that dynamic biped locomotion is a special case of dynamic nonprehensile manipulation in all aspects; we prove that ZMP (zero-moment point) and FRI (zoot rotation indicator) are special cases of PRI (palm rotation indicator). Simulations and experiments corresponding to simple examples support the results

On the Domination Polynomial of Graphs

, M.Sc. Thesis Sharif University of Technology Ebrahimi, Zeinab (Author) ; Akbari, Saeed (Supervisor)

Some Applications of Combinatorial Nullstellensatz in Graph Theory and Combinatorics

, M.Sc. Thesis Sharif University of Technology Fakhari, Amin (Author) ; Akbari, Saeed (Supervisor)

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 Jokar, Effat (Author) ; 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...

Chemically Modified Electrodes Based on Conducting Polymers and Carbon Nanotubes: Application to Voltammetric Determination of Some Biological and Pharmaceutical Compounds

, M.Sc. Thesis Sharif University of Technology Asadian, Elham (Author) ; Shahrokhian, Saeed (Supervisor)

Abstract

There are high attractions in the development of conducting polymer (CP) coatings to improve the electrochemical properties and biocompatibility of electrodes in the area of biosensors. In the first part of this thesis, a new type of modified electrodes, constructing multi-walled carbon nanotubes (MWCNTs) and polypyrrole is prepared in a layer-by-layer process. In this procedure, the glassy carbon electrode is casted first by a drop suspension of MWCNTs, leading to formation a thin film on its surface. In the second step, electrochemical polymerization of pyrrole in the presence of tiron (used as doping anion) is performed on the surface of the MWCNTs pre-coated electrode. The modification...

Probing the Electrochemical Properties of Gold Electrode Modified with Edge-Functionalized Graphene and its Application

, M.Sc. Thesis Sharif University of Technology Aghajani, Talin (Author) ; Shahrokhian, Saeed (Supervisor)

Abstract

In the present work, edge-functionalaized graphene was used as electrode material and its electrochemical properties were systematically characterized by electrochemical impedance spectroscopy and cyclic voltammetry. Two methods were applied to modify the gold electrode surface. First method was the self assembling process of graphene nanosheets on gold electrode surface. Second method was simply casting specific amounts of graphene suspension on the gold electrode surface. Nyquist plots show decrease of the charge transfer resistance on the electrode surface at both cases. In cyclic voltammetry studies, first electrode shows no significant changes while the second electrode exhibits...

Probabilistic Methods in Graph Coloring

, M.Sc. Thesis Sharif University of Technology Ahadi, Arash (Author) ; Akbari, Saeed (Supervisor)

Abstract

Graph Theory and Combinatorial Analysis like the other branches of science use the probability for solving their problems. At the first , we will introduce the most common tools from probability used in Discrete Mathematics, such as “The Lovasz Local Lemma”. Most of them are based on Linearity of Expectation, Concentration Theorems and some other innovative methods such as Deletation Method. We will present different examples for these techniques. Also we will introduce “Random Graphs” and their importance. Specially we will explain how to use “Threshold Functions” to obtain different properties about the majority of graphs. Rainbow Connection, is a natural and interesting quantifiable way...

Electrochemical Determination of Tyrosine and Tryptophan at the Surface of Pyrolytic Graphite Electrode Modified with Multi-Walled Carbon Nanotubes, New Coccine and Nitrazine

, M.Sc. Thesis Sharif University of Technology Ebrahimi, Shiva (Author) ; Shahrokhian, Saeed (Supervisor)

Abstract

At the first part of this thesis, a pyrolitic graphite electrode (PGE) modified with new coccine/multi-walled carbon nanotubes film (NC/MWCNT) was applied as a sensitive electrochemical sensor for determination and study of electrochemical behavior of tyrosine (Tyr) in aqueous solutions. The results showed that NC/MWCNT caused a remarkable increase in the peak current so the NC/MWCNT/PGE electrode surface was far more sensitive to the concentration of Tyr than the PGE surface. The determination of Tyr was investigated by linear sweep voltammetry (LSV). Experimental parameters, such as scan rate, pH and amount of the modifier used on the PGE surface were optimized by monitoring the LSV...

The Regular Graph Retated to Rings

, M.Sc. Thesis Sharif University of Technology Jamaali, Mohsen (Author) ; Akbari, Saeed (Supervisor)

Abstract

There are many papers in which some graphs are assigned to algebraic structures such as rings groupsThe concept of regular graph related to a ring was rst investigated by DF Anderson and A Badawi in Assume that R is a commutative ring and Z??R denotes the set of zerodivisors of R and Reg??R R n Z??R The regular graph of R which is denoted by Reg????R is a graph whose vertex set is Reg??R and two vertices x and y are adjacent if and only if x y ?? Z??R This can be generalized to a non commutative ring For the vertex set we consider the set of left ??right zerodivisors and join two elements if their sum is a left ??right zerodivisor Let R be the ring of n n matrices over a eld F with...

Zero-sum Flows in Graphs

, M.Sc. Thesis Sharif University of Technology Nategh, Emisa (Author) ; Akbari, Saeed (Supervisor)

Abstract

For an undirected graph G, a zero-sum flow is an assignment of non-zero real numbers on the edges of G such that the total sum of all edges incident with any vertex of G is zero. A zero-sum k-flow for a graph G is a zero-sum flow with labels from the set {±1, . . . , ±(k ? 1)}. In this thesis for a graph G, a necessary and sufficient condition forthe existence of zero-sum flow is given. It has been conjectured that if a graph G has azero-sumflow, then it has a zero-sum 6-flow. Also, it has been proved that this conjectureand Bouchet’s Conjecture for bidirected graphs are equivalent. It is shown that the con-jecture is true for 2-edge connected bipartite graphs, and every r-regular graph...

Application of Pore Network Modeling in Study of Rock Typing Algorithms

, M.Sc. Thesis Sharif University of Technology Sistan, Morteza (Author) ; Jamshidi, Saeed (Supervisor)

Abstract

One of the most important issues in modeling and simulation of reservoirs is determination of different rock types or Rock Typing. In this study, after a brief review of some conventional methods for rock typing, their capabilities have been investigated. In this way, for the first time, pore network modeling is used as a tool for validating the rock typing methods. By using flow simulation in porous medium with pore network modeling approach, similar rock types data have been generated and these artificially data have been used for validating of rock typing methods. To form more realistic pore networks, both regular and irregular pore network have been modeled and analyzed. Pore size...