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tizpaz-niari--saeed
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Analysis and Evaluation of Router Security Based on a Routing Protocol
, M.Sc. Thesis Sharif University of Technology ; Jahangir, Amir Hossein (Supervisor)
Abstract
The importance of routers in information transfer among networks is critical. Thus, vulnerabilities and security deficiencies in routers and the related services like routing protocols can be destructive not only for some hosts, but also for the whole network. Hence, it is necessary that 1) vulnerabilities related to the routers and their services be evaluated and analyzed, and 2) the functional aspects of routers related to the vulnerabilities be formally modeled and analyzed. In this thesis, we present a method for the evaluation and the analysis of OSPF routing protocol from the security point of view. First, reported vulnerabilities on the OSPF are collected and evaluated by a...
Verification of OSPF vulnerabilities by colored petri net
, Article SIN 2013 - Proceedings of the 6th International Conference on Security of Information and Networks ; November , 2013 , Pages 102-109 ; 9781450324984 (ISBN) ; Jahangir, A. H ; Sharif University of Technology
2013
Abstract
Routers and routing protocols are critical parts of a network infrastructure. OSPF is one of the most important routing protocols, and therefore its vulnerabilities can be very destructive. This makes its security analysis critical. There are many reported and potential vulnerabilities in OSPF protocol. Considering the complexity and the ambiguity of its description in RFC 2328, it is very valuable to design a formal model of the protocol and analyze the vulnerabilities of its critical parts. In this paper, some challenging parts of OSPF protocol along with attack scenarios are modeled by means of Colored Petri Net in CPN Tools environment. Then, the reported vulnerabilities are analyzed by...
Modeling Multi-path Covering Routing Problem
, M.Sc. Thesis Sharif University of Technology ; Koorosh, Eshghi (Supervisor)
Abstract
The location problem is one of the main topics at the strategic level. This problem is investigated along with many areas such as network design and path covering problems. Routing between source and destination nodes is done in such a way that maximizes traffic coverage and reduces costs as much as possible. Routing problems are considered in goods distribution areas and urban transit systems. Goods distribution from set of cross-docks can help to reduce costs and improve resource efficiency. So, this topic is considered in this research and a suitable model is proposed. Defining and developing of the road and rail transportation networks are main topics in urban traffic management which...
CFD Simulation and Analysis of Heat Pipe Heat Exchanger Radiator
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor)
Abstract
Due to the development of heat pipes in different industries and special characteristics of heat pipes, in this study, it has been tried using computational fluid dynamics (CFD) method to simulate a heat pipe heat exchanger that can be a replacement for the normal radiator. The experimental model of this heat exchanger has been tested at past studies and the numerical simulation of the heat exchanger will analyze at present study. The use of heat pipe in the car radiator has many advantages such as reducing fluid pressure drop through the heat exchanger, high reliability due to the particular structure of the heat exchanger (individual performance of each heat pipe) and improving heat...
Topology analysis of manufacturing service supply–demand hyper-network considering QoS properties in the cloud manufacturing system
, Article Robotics and Computer-Integrated Manufacturing ; Volume 72 , 2021 ; 07365845 (ISSN) ; Eshgi, K ; Fatahi Valilai, O ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Cloud Manufacturing (CMfg), a new manufacturing paradigm, enables an opportunity for manufacturing enterprises to respond to a wide variety of demands. The CMfg concept integrates the distributed resources and capacities in a shared economy, transfers them to the virtual manufacturing services with various quality of service (QoS) properties. These services are invoked to collaborate in producing customized demands with specific functional and non-functional properties. The operational perspective of the service-demand matching problem is considered more in the literature; however, it is a challenging problem in the CMfg ecosystem. This paper evaluates the service-demand matching problem...
Adaptive capacity management in cloud manufacturing hyper-network platform: Case of COVID-19 equipment production
, Article International Journal of Management Science and Engineering Management ; Volume 17, Issue 4 , 2022 , Pages 239-258 ; 17509653 (ISSN) ; Eshghi, K ; Fatahi Valilai, O ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Cloud Manufacturing (CMfg) is a service-oriented manufacturing (SOM) paradigm that provides a dynamic, scalable, and virtualized working ecosystem. The CMfg collaborative structure can be modeled as a hyper-network-based service-demand matching architecture. It is enriched with quality of service (QoS) characteristics to produce customized products in a stable and reliable network. This stability should be considered in the overall manufacturing network mechanism. This paper has provided adaptive strategies utilizing available resources and capacities to enhance the system’s stability and reliability against the unexpected events. The capabilities of the enhanced framework are utilized to...
Developing Mathematical Model for Service-Demand Matching in Cloud Manufacturing Network
, Ph.D. Dissertation Sharif University of Technology ; Eshghi, Kourosh (Supervisor) ; Fatahi Valilai, Omid (Supervisor)
Abstract
Cloud Manufacturing (CMfg) is a service-oriented manufacturing (SOM) paradigm that provides a dynamic, scalable, and virtualized working ecosystem. The CMfg collaborative structure can be modeled as a hyper-network-based service-demand matching architecture. It is enriched with quality of service (QoS) characteristics to produce customized products in a stable and reliable network. This stability should be considered in the overall manufacturing network mechanism. This Thesis has developed a multi-dimentional model and improved it by providing absorptive and adaptive strategies utilizing available resources and capacities to enhance the system’s stability and reliability against the...
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, 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...
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 ; 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 ; 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 ; 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 ; Akbari, Saeed (Supervisor)Some Applications of Combinatorial Nullstellensatz in Graph Theory and Combinatorics
, M.Sc. Thesis Sharif University of Technology ; 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
;
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
;
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...
Research on Influences of Coating on Low Cycle Fatigue Properties of Ni-Base Superalloy René 80
, Ph.D. Dissertation Sharif University of Technology ; Nategh, Saeed (Supervisor)
Abstract
In this thesis, based on the taking-off and landing of aircraft with GE 21-J85 turbine, the low cycle fatigue (LCF) test for superalloy used in first stage blades is considered. The LCF tests were performed on both coated and uncoated Rene 80 which are used in GE 21-J85 turbine at R = (min/max) = 0, strain rate of 2 10-3 s-1 and 760oC, 871oC and 982oC. To produce specimens, an investment casting method was used so that adequate amount of polycrystalline round bars could be obtained. The specimens were all homogenized and solution treated. After the inspection, some specimens were coated with pack cementation method in CODEP-B powder in H2 atmosphere. The coated and uncoated specimens all...
Voltammetric Determination of Tryptophan and 5-Hydroxytryptophan Using Graphite Electrode Modified with a Thin Film of Graphite/Diamond Nano-mixture And Determination of omeprazole Using Graphite Electrode
,
M.Sc. Thesis
Sharif University of Technology
;
Shahrokhian, Saeed
(Supervisor)
Abstract
At the first part of this thesis, a pyrolitic graphite electrode (PGE) modified with graphite/nanodiamond film (GND) was applied as a sensitive electrochemical sensor for determination and study of electrochemical behavior of tryptophan (Trp) and 5-hydroxytryptophan (5-HTP) in aqueous solutions. The results showed that GND caused a remarkable increase in the peak currents so the GND/PGE electrode surface was more sensitive to the concentration of Trp and 5-HTP than the PGE surface. The determination of Trp and 5-HTP were investigated by stripping voltammetry. Experimental parameters such as scan rate, pH, accumulation conditions and amount of the modifier used on the PGE surface were...
Simultaneous Voltammetric Determination of Epinephrine and UricAcid in Presence of Ascorbic Acid Using Pyrolytic Graphite Electrode Modified with Nano- diamond/graphite Film & Voltammetric Determination of Levothyroxine at the Surface of Edge Plane Pyrolytic Graphite Electrode
,
M.Sc. Thesis
Sharif University of Technology
;
Shahrokhian, Saeed
(Supervisor)
Abstract
Part 1: A novel modified pyrolytic graphite electrode with nanodiamond/graphite was fabricated. The electrochemical response characteristics of the modified electrode toward the epinephrine (EN) and uric acid (UA) are studied by means of cyclic and linear sweep voltammetry. The structural morphology and thickness of the film was characterized by SEM technique.The prepared electrode shows an excellent catalytic activity in the electrochemical oxidation of EN and UA, leading to remarkable enhancements in the corresponding peak currents and lowering the peak potentials. The prepared modified electrode acts as a highly sensitive sensor for simultaneous determination of EN and UA in the presence...
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 ; 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...