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akbari--hamid
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Designing an Estimation of Distribution Algorithm Based on Data Mining Methods
, M.Sc. Thesis Sharif University of Technology ; Beigy, Hamid (Supervisor)
Abstract
Estimation of distribution algorithms (EDA) are optimization methods that search the solution space by building and sampling probabilistic models. The linkage tree genetic algorithm (LTGA), which can be considered an estimation of distribution algorithm, uses hierarchical clustering to build a hierarchical linkage model called the linkage tree, and gene-pool optimal mixing algorithm to generate new solutions. While the LTGA performs very well on problems with separable sub-problems, its performance deteriorates on ones with overlapping sub-problems. This thesis presents a comparison of the effect of different pre-constructed models in the LTGA's performance. Several important factors that...
Fabrication and Investigation of Printing Mechanism in order to Deposit Semiconductor thin Films for Photovoltaic Devices
, M.Sc. Thesis Sharif University of Technology ; Taghavinia, Nima (Supervisor)
Abstract
Finding a reliable and reproducible method to deposit thin films of semiconductors is a huge leap forward in order to fabricate nano-structured solar cells. As the third and forth generation of solar cells are based on semiconductors which are soluble in solvents and can be deposited with solution-based methods, finding a proper printing mechanics can lead to cheap solar panels. In this thesis we have designed and fabricated an apparatus to deposit lead iodide films. These thin films can be used to fabricate perovskite solar cells which are based on methylammonium lead iodide perovskite. We have also investigated different inks consisting of different additives and solvents best suited for...
Application of Data Mining in Customer Relationship Management
, M.Sc. Thesis Sharif University of Technology ; Akbari, Mohammad Reza (Supervisor)
Abstract
Nowadays the issue of recognizing customer’s needs and leading different activities of industrial units to obviate such needs are important concerns and are coined as “Customer Relationship Management” in business literature. What’ s more, with the development of information technology ,creating the possibility to gather, warehouse and analyze huge amount of data quickly, “Data Mining” subject is presented to analysts and experts as a powerful tool. Currently in many aspects of CRM, analysts are considering Data Mining techniques in order to identify customers’ behavior pattern, performance and predict customers’ behavior and to specify their desires based on this pattern. This Thesis is to...
Photodynamic Therapy by Er And Yb Doped TiO2 Upconversion Nanoparticles
, M.Sc. Thesis Sharif University of Technology ; Maddah Hosseini, Hamid Reza (Supervisor)
Abstract
Photodynamic therapy that has been developed over last century, now has become more widely used medical tool for the treatment of various diseases such as cancer. This technique involves delivery of photosensitizing drugs, irradiation of light and motivation of drugs. The limitation of light penetration in body tissue, may resolve by application of upconversion nanoparticles. Upconverting nanoparticles could help treatment of cancer tumors in deep or critical points of body by converting high penetrating Near-Infrared emissions to higher energy visible emissions. In the present work, rare earth elements doped TiO2 nanoparticles are synthesized. The photodynamic properties of rare earth...
Processor Allocation for Future Multi-Core Chip-Multiprocessor
, M.Sc. Thesis Sharif University of Technology ; Sarbazi Azad, Hamid (Supervisor)
Abstract
Since 2005, processor designers have increased core counts to exploit Moore’s Law scaling, rather than focusing on single-core performance. For decades, this approach provides desired performance for parallel and multithreaded workloads. On the other hand, rising of utilization wall limits the number of transistors that can be powered on in chip and result in a large region to be dark. So, same as before trend for performance scaling in future multi processor, an appropriate architecture is essential. There are some structures for this era which used specialization approach to cope with the limited power budget. Therefore, in this thesis, we propose a general-purpose platform that provides...
A Complex Network Model for Peer-to-Peer Streaming Networks
, M.Sc. Thesis Sharif University of Technology ; Akbari, Behzad (Supervisor) ; Rabiee, Hamid Reza (Supervisor)
Abstract
Complex networks science have become the major method in the modeling of topological features of networks and graphs. Although file sharing Peer-to-Peer systems can be modeled by networks with un-weighted nodes and links, using these networks for Peer-to-Peer streaming systems have not led to a suitable model.In this research, we aim to model Peer-to-Peer streaming networks with weighted nodes and weighted links so that present the performance of nodes and the amount of streaming that is transmitted between nodes respectively. Due to lack of information about upload bandwidth distribution in networks we assume this distribution as uniform. Because of dynamics of network, this distribution...
Efficient Content Partitioning and Block Scheduling in Mesh-Based Peer-to-Peer Live Video Streaming Systems
, M.Sc. Thesis Sharif University of Technology ; Rabiee, Hamid Reza (Supervisor) ; Akbari, Behzad (Co-Advisor)
Abstract
In recent years peer-to-peer video streaming systems have become the major alternative for traditional client-server models, and several P2P streaming applications have attracted a large number of users on the Internet. In a mesh based P2P streaming architecture a video stream is portioned into video blocks and each peer pulls these video blocks from its neighbors. Since the uplink bandwidth of each peer is its main constraint in transmission video blocks, efficient block scheduling can play an important role in improving the perceived video quality by peers. Moreover, the granularity of video blocks can have a significant impact on the performance of the system. In this thesis, we propose...
Targeted Delivery of Curcumin by Mesoporous Silica Nanoparticle Coated with Liposome
, M.Sc. Thesis Sharif University of Technology ; Abdekhodaie, Mohammad Jafar (Supervisor) ; Akbari, Hamid (Supervisor)
Abstract
Several studies based on anti- cancer, anti- metastatic and anti- tumor effects of curcumin have been reported . Besides these benefits, the therapeutic efficacy of curcumin is limited due to its poor aqueous solubility, extensive first-pass metabolism, inadequate tissue absorption and degradation at alkaline pH, which severely diminishes its bioavailability. In this project we seek to solve some of the problems with nanoscience to work more effectively. In the past decade, mesoporous silica nanoparticles (MSNs) have found widespread application as controlled drug delivery systems. Recent reports on the design of capped and gated MSN-based systems have shown promise in preventing premature...
On the Finiteness of Noetherian Rings with Finitely Many Regular Elements
, Article Communications in Algebra ; Vol. 42, issue. 7 , 2014 , pp. 2869-2870 ; ISSN: 00927872 ; Heydari, F
2014
Abstract
Let R be a left Noetherian ring and ZD(R) be the set of all zero-divisors of R. In this paper, it is shown that if RZD(R) is finite, then R is finite
Multicolored spanning subgraphs in G-colorings of complete graphs
, Article Ars Combinatoria ; Volume 111 , 2013 , Pages 145-159 ; 03817032 (ISSN) ; Zare, S
2013
Abstract
Let G = {g1,...,gn} be a finite abelian group. Consider the complete graph with the vertex set {g1.....,.....g n}. The G-coloring of Kn is a proper edge coloring in which the color of edge {gi,gj} gi g i + gj, 1 ≤ i < 3 ≤ n. We prove that in the G-coloring of the complete graph Kn, there exists a multicolored Hamilton path if G is not an elementary abelian 2-group. Furthermore, we show that if n is odd, then the G-coloring of Kn can be decomposed into multicolored 2-factors and there are exactly lr/2 multicolored r-uniform 2-factors in this decomposition where lr is the number of elements of order r in G, 3 ≤ r ≤ n. This provides a generalization of a recent result due to Constantine which...
Optimizing Transmisson from Distant Wind Farms
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Hamid (Supervisor)
Abstract
Wind power is site dependent and is by nature partially dispatchable. Furthermore, good wind sites are far from grid. Due to these problems, and along with the existing limitations in the transmission networks, a comprehensive analysis over an extended time is needed to properly explore all potential wind sites for wind capacity allocation. This problem is computationally expensive and decomposition methods are required to break down this problem. Here Benders decomposition approach is used, which is a popular technique for solving large-scale problems, to decompose the original problem into a master and a subproblem. The master problem is a linear problem, which allocates wind capacity to...
Left artinian algebraic algebras
, Article Algebra Colloquium ; Volume 8, Issue 4 , 2001 , Pages 463-470 ; 10053867 (ISSN) ; Sharif University of Technology
2001
Abstract
Let R be a left artinian central F-algebra, T(R) = J(R) + [R,R], and U(R) the group of units of R. As one of our results, we show that, if R is algebraic and char F = 0, then the number of simple components of R = R/J(R) is greater than or equal to dimF R/T(R). We show that, when char F = 0 or F is uncountable, R is algebraic over F if and only if [R, R] is algebraic over F. As another approach, we prove that R is algebraic over F if and only if the derived subgroup of U(R) is algebraic over F. Also, we present an elementary proof for a special case of an old question due to Jacobson. © Inst. Math. CAS 2001
Two conjectures on uniquely totally colorable graphs
, Article Discrete Mathematics ; Volume 266, Issue 1-3 , 2003 , Pages 41-45 ; 0012365X (ISSN) ; Sharif University of Technology
2003
Abstract
In this paper we investigate two conjectures proposed in (Graphs Combin. 13 (1997) 305-314). The first one is uniquely totally colorable (UTC) conjecture which states: Empty graphs, paths, and cycles of order 3k, k a natural number, are the only UTC graphs. We show that if G is a UTC graph of order n, then Δn/2+1, where Δ is the maximum degree of G. Also there is another question about UTC graphs that appeared in (Graphs Combin. 13 (1997) 305-314) as follows: If a graph G is UTC, is it true that in the proper total coloring of G, each color is used for at least one vertex? We prove that if G is a UTC graph of order n and in the proper total coloring of G, there exists a color which did not...
Identification of the Set of Single Nucleotide Variants in Genome Responsible for the Differentiation of Expression of Genes
, M.Sc. Thesis Sharif University of Technology ; Rabiee, Hamid Reza (Supervisor) ; Beigi, Hamid (Supervisor)
Abstract
Single nucleotide polymorphs, There are changes caused by a mutation in a nucleotide in the Dena sequence. Mononucleotide polymorphisms are the most common type of genetic variation. Some of these changes have little or no effect on cells, while others cause significant changes in the expression of cell genes that can lead to disease or resistance to certain diseases. Because of the importance of these changes and their effect on cell function, the relationships between these changes are also important. Over the past decade, thousands of single disease-related mononucleotide polymorphisms have been identified in genome-related studies. Studies in this field have shown that the expression of...
Synthesis & Characterization of Au-HKUST-1 Nanocomposite and Evaluation of Plasmonic Properties of Gold Nanoparticles in this Nanocomposite
, M.Sc. Thesis Sharif University of Technology ; Madaah Hosseini, Hamid Reza (Supervisor)
Abstract
In the past few years, many research works on the controllable integration of metal nanoparticles and metal-organic frameworks were done, since the obtained composite material shows a synergism effect in catalysis and photocatalysis, drug delivery applications, gas, and energy storage, as well as sensing. For the first time, in this study, we employed template-assisted growth to synthesize Au-HKUST-1 Nanocomposite. XRD analysis entirely confirms that employing this strategy in synthesizing Au-HKUST-1 was wholly successful, and the plasmonic properties of this nanostructure were studied via UV-visible spectroscopy. In the course of synthesis, gold nanoparticles with 70nm diameter were...
Synthesis of Magnetite (Fe3O4)-Avastin Nanocomposite as a Potential Drug for AMD Treatment
, M.Sc. Thesis Sharif University of Technology ; Maddah Hosseini, Hamid Reza (Supervisor) ; Delavary, Hamid (Co-Advisor)
Abstract
Age-related macular degeneration (AMD) is the most common cause of vision loss in those aged over 50. There are two main types of AMD, Wet and Dry form. Wet AMD is more severe though more treatable. There are three conventional treatments for AMD including laser therapy, surgery and intravitreal injection of anti-VEGF into the eye. Delivery of drugs to the posterior segment of the eye is still challenging and several implants and devices are currently under investigation for their ability to stimulate the retina, producing visual percepts. The application of intravitreal bevacizumab (Avastin) has expanded tremendously from the time of its introduction into ophthalmic care since 3 years ago....
Detection of Central Nodes in Social Networks
, Ph.D. Dissertation Sharif University of Technology ; Movaghar, Ali (Supervisor) ; Rabiee, Hamid Reza (Supervisor)
Abstract
In analyzing the structural organization of many real-world networks, identifying important nodes has been a fundamental problem. The network centrality concept deals with the assessment of the relative importance of network nodes based on specific criteria. Central nodes can play significant roles on the spread of influence and idea in social networks, the user activity in mobile phone networks, the contagion process in biological networks, and the bottlenecks in communication networks. High computational cost and the requirement of full knowledge about the network topology are the most significant obstacles for applying the general concept of network centrality to large real-world social...
Influence of nanoclay on morphology, mechanical properties and deformation mechanism of Polystyrene
, Article Polymer - Plastics Technology and Engineering ; Vol. 53, issue. 2 , 2014 , p. 156-161 ; ISSN: 03602559 ; Bagheri, R ; Sharif University of Technology
2014
Abstract
Polystyrene/organoclay nanocomposites were prepared by melt intercalation method in this research. Morphology, tensile and impact properties and deformation mechanism of the samples were studied. To study the structure of nanocomposites, X-ray diffraction and transmission electron microscopy techniques are utilized. The deformation mechanisms of different samples were examined via reflected and transmitted optical microscopy. The results reveal that incorporation of organoclay affects structure, mechanical properties and deformation mechanism of nanocomposite. Introduction of organoclay can facilitate initiation and growth of crazing mechanism in polystyrene at both conditions of loadings,...
The regular graph of a non-commutative ring
, Article Electronic Notes in Discrete Mathematics ; Vol. 45, issue , January , 2014 , pp. 79-85 ; ISSN: 15710653 ; Heydari, F ; Sharif University of Technology
2014
Abstract
Let R be a ring and Z(R) be the set of all zero-divisors of R. The total graph of R, denoted by T(Γ(R)) is a graph with all elements of R as vertices, and two distinct vertices x, y∈R are adjacent if and only if x+y∈Z(R). Let the regular graph of R, Reg(Γ(R)), be the induced subgraph of T(Γ(R)) on the regular elements of R. In 2008, Anderson and Badawi proved that the girth of total graph and regular graph of a commutative ring are contained in the set {3, 4, ∞}. In this paper, we extend this result to an arbitrary ring (not necessarily commutative). Also, we prove that if R is a reduced left Noetherian ring and 2∈Z(R), then the chromatic number and the clique number of Reg(Γ(R)) are the...
The regular graph of a noncommutative ring
, Article Bulletin of the Australian Mathematical Society ; Vol. 89, issue. 1 , February , 2014 , pp. 132-140 ; ISSN: 00049727 ; Heydari, F ; Sharif University of Technology
2014
Abstract
Let R be a ring and Z(R) be the set of all zero-divisors of R. The total graph of R, denoted by (TΓ (R)) is a graph with all elements of R as vertices, and two distinct vertices x, y in R are adjacent if and only if x + y Z(R). Let the regular graph of R, Reg (Γ(R)), be the induced subgraph of T(Γ (R)) on the regular elements of R. In 2008, Anderson and Badawi proved that the girth of the total graph and the regular graph of a commutative ring are contained in the set { 3, 4,} . In this paper, we extend this result to an arbitrary ring (not necessarily commutative). We also prove that if R is a reduced left Noetherian ring and 2 Z(R), then the chromatic number and the clique number of Reg...