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, M.Sc. Thesis Sharif University of Technology ; AliReza (Supervisor)
Abstract
After positivists, that argue the structure and growth of scientific knowledge is rational, and constructivists, that argue science is based on irrational basis, analysis of structure and growth of scientific knowledge, in few decades ago, has developed from cognitive perspective. In this approach, i.e cognitive phase of philosophy of science, the role of concepts, that organized around hierarchies, become important. In current dissertation, we have considered views of paul Thagard, the cognitive scientist, about conceptual systems, and structure of science from cognitive approach. Thagard, postulating the truth of scientific developments, describes mental representations and processes in...
Using Complex Network Metrics for Evaluating the Influence of Conference and Journal Papers in Computer Science
,
M.Sc. Thesis
Sharif University of Technology
;
Jalili, Mahdi
(Supervisor)
Abstract
Journals and conferences in computer science are the major venue for publishing new achievement in the field. It is an expert opinion that a number of top conferences in computer science are even more important than journals. In this work we aim at studying this in terms of citation analysis. To this end, we took 100 top journals and 63 top conferences and extracted their citation graph through Scopus dataset. We then constructed the citation graph in which the nodes were the journals and conferences and the links corresponded to the citations of the papers. We used various measures to rank the nodes in the graph. The ranking methods included Prestige, PageRank, Eigenfactor, HITS and SALSA....
Zamin, an agent based artificial life model
, Article Proceedings - HIS'04: 4th International Conference on Hybrid Intelligent Systems, Kitakyushu, 5 December 2004 through 8 December 2004 ; 2005 , Pages 160-165 ; 0769522912 (ISBN) ; Shouraki, S. B ; Zadeh, S. H ; Ziaie, P ; Lucas, C ; Ishikawa M ; Hashimoto S ; Paprzycki M ; Barakova E ; Yoshida K ; Koppen M ; Corne D.M ; Abraham A ; Sharif University of Technology
2005
Abstract
Zamin artificial life model is designed to be a general purpose environment for researches on evolution of learning methods, living strategies and complex behaviors and is used in several studies thus far. As a main target for Zamin's design has been its expandability and ease of problem definition, a new agent based structure for this artificial world is introduced in this paper, which is believed to be much easier to use and extend. In this new model, all control and world running processes are done by agents. Therefore, any change in world processes does not require recoding the main engine and can be done just by altering the behavior of one or some agents. To have an easier interface...
White space regions
, Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 22 January 2011 through 28 January 2011, Novy Smokovec ; Volume 6543 LNCS , 2011 , Pages 226-237 ; 03029743 (ISSN) ; 9783642183805 (ISBN) ; Fazli, M ; Ghodsi, M ; Safari, M ; Saghafian, M ; Tavakkoli, M ; Sharif University of Technology
2011
Abstract
We study a classical problem in communication and wireless networks called Finding White Space Regions. In this problem, we are given a set of antennas (points) some of which are noisy (black) and the rest are working fine (white). The goal is to find a set of convex hulls with maximum total area that cover all white points and exclude all black points. In other words, these convex hulls make it safe for white antennas to communicate with each other without any interference with black antennas. We study the problem on three different settings (based on overlapping between different convex hulls) and find hardness results and good approximation algorithms
Web page classification using social tags
, Article 2009 IEEE International Conference on Social Computing, 29 August 2009 through 31 August 2009 ; Volume 4 , 2009 , Pages 588-593 ; 9780769538235 (ISBN) ; Abolhassani, H ; Rahmani, H ; Nobakht, B ; Sharif University of Technology
Abstract
Social tagging is a process in which many users add metadata to a shared content. Through the past few years, the popularity of social tagging has grown on the web. In this paper we investigated the use of social tags for web page classification: adding new web pages to an existing web directory. A web directory is a general human-edited directory of web pages. It classifies a collection of pages into a wide range of hierarchical categories. The problem with manual construction and maintenance of web directories is the significant need of time and effort by human experts. Our proposed method is based on applying different automatic approaches of using social tags for extending web...
Using social annotations for search results clustering
, Article 13th International Computer Society of Iran Computer Conference on Advances in Computer Science and Engineering, CSICC 2008, Kish Island, 9 March 2008 through 11 March 2008 ; Volume 6 CCIS , 2008 , Pages 976-980 ; 18650929 (ISSN); 3540899847 (ISBN); 9783540899846 (ISBN) ; Khayyamian, M ; Abolhassani, H ; Sharif University of Technology
2008
Abstract
Clustering search results helps the user to overview returned results and to focus on the desired clusters. Most of search result clustering methods use title, URL and snippets returned by a search engine as the source of information for creating the clusters. In this paper we propose a new method for search results clustering (SRC) which uses social annotations as the main source of information about web pages. Social annotations are high-level descriptions for web pages and as the experiments show, clustering based on social annotations yields good clusters with informative labels. © 2008 Springer-Verlag
Using similarity flooding for extracting similar parts of proteins
, Article International MultiConference of Engineers and Computer Scientists 2007, IMECS 2007, Kowloon, 21 March 2007 through 23 March 2007 ; 2007 , Pages 497-503 ; 20780958 (ISSN) ; 9789889867140 (ISBN) ; Salehi, S ; Ghodsi, M ; Sharif University of Technology
2007
Abstract
Proteins are the main players in the game of life. Good understanding of their structures, functions, and behaviors leads to good understanding of drugs, diseases, and thus our health. So, much effort has been done to study and categorize proteins. Nowadays, tens of thousands of proteins have been found. Moreover, the problem of comparing the proteins is hard. Therefore efficient methods are needed to deal with this problem. In this paper, we used one important computational geometric method and one graph matching method: "Delaunay Tetrahedral-ization" and "Similarity Flooding" to propose a new idea to extract similar parts of proteins by combining both of these methods
Using minimum matching for clustering with balancing constraints
, Article 2009 Second ISECS International Colloquium on Computing, Communication, Control, and Management, CCCM 2009, Sanya, 8 August 2009 through 9 August 2009 ; Volume 1 , 2009 , Pages 225-228 ; 9781424442461 (ISBN) ; Abolhassani, H ; Shirali Shahreza, M. H ; Yangzhou University; Guangdong University of Business Studies; Wuhan Institute of Technology; IEEE SMC TC on Education Technology and Training; IEEE Technology Management Council ; Sharif University of Technology
2009
Abstract
Clustering is a major task in data mining which is used in many applications. However, general clustering is inappropriate for many applications where some constraints should be applied. One category of these constraints is the cluster size constraint. In this paper, we propose a new algorithm for solving the clustering with balancing constraints by using the minimum matching. We compare our algorithm with the method proposed by Banerjee and Ghosh that uses stable matching and show that our algorithm converge to the final solution in fewer iterations. ©2009 IEEE
Unsupervised coreference resolution using a graph labeling approach
, Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) ; Vol. 8387 LNAI , 2014 , pp. 93-103 ; ISSN: 03029743 ; ISBN: 978-3319089577 ; GhassemSani, G ; Sharif University of Technology
Abstract
In this paper, we present a new unsupervised coreference resolution method, that models coreference resolution as a graph labeling problem. The proposed approach uses an incremental graph development method that hierarchically deploys coreference features from higher precision to lower ones. Then, a relaxation labeling method is used for solving the graph labeling problem
Truthful and secure routing in Ad Hoc networks
, Article 2008 International Symposium on Computer Science and its Applications, CSA 2008, Hobart, TAS, 13 October 2008 through 15 October 2008 ; October , 2008 , Pages 369-376 ; 9780769534282 (ISBN) ; Ghodsi, M
2008
Abstract
Cooperation among nodes is vital in wireless networks since in such networks nodes depend on each other for routing packets. However, cooperation in such operations consumes nodes recourses such as battery and bandwidth. Therefore, it is necessary to design incentive mechanisms to enforce nodes to forward packets when the source and destination of the packet are other nodes. We study routing in wireless networks from a game theoretic view point. Based on this view, the network consists of greedy and selfish nodes who accept payments for forwarding data for other nodes if the payments cover their individual costs incurred by forwarding data. Also, route falsification attacks are easy to...
Torsional sensitivity of the first four modes of an AFM cantilever with a sidewall probe using analytical method
, Article Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference 2009, DETC2009 ; Volume 6 , 2009 , Pages 617-622 ; 9780791849033 (ISBN) ; Rahaeifard, M ; Ahmadian, M. T ; Sharif University of Technology
Abstract
In this study, using analytical method, the torsional resonant frequency and torsional sensitivity of the first four modes of an AFM cantilever with sidewall probe including a horizontal cantilever and a vertical extension is analyzed and a closed form for torsional sensitivity of the probe is derived. In addition, the effect of relative parameters such as ratio of vertical extension length to horizontal cantilever length is investigated. According to this study, the results show that as contact stiffness increases, the resonant frequencies of all vibration modes increases until they reach constant values at very high values of contact stiffness. It is also can be found that low-order modes...
The visual object tracking VOT2013 challenge results
, Article Proceedings of the IEEE International Conference on Computer Vision ; 2013 , Pages 98-111 ; 9781479930227 (ISBN) ; Pflugfelder, R ; Leonardis, A ; Matas, J ; Porikli, F ; Čehovin, L ; Nebehay, G ; Fernandez, G ; Vojíř, T ; Gatt, A ; Khajenezhad, A ; Salahledin, A ; Soltani-Farani, A ; Zarezade, A ; Petrosino, A ; Milton, A ; Bozorgtabar, B ; Li, B ; Chan, C. S ; Heng, C ; Ward, D ; Kearney, D ; Monekosso, D ; Karaimer, H. C ; Rabiee, H. R ; Zhu, J ; Gao, J ; Xiao, J ; Zhang, J ; Xing, J ; Huang, K ; Lebeda, K ; Cao, L ; Maresca, M. E ; Lim, M. K ; ELHelw, M ; Felsberg, M ; Remagnino, P ; Bowden, R ; Goecke, R ; Stolkin, R ; Lim, S. Y. Y ; Maher, S ; Poullot, S ; Wong, S ; Satoh, S ; Chen, W ; Hu, W ; Zhang, X ; Li, Y ; Niu, Z ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2013
Abstract
Visual tracking has attracted a significant attention in the last few decades. The recent surge in the number of publications on tracking-related problems have made it almost impossible to follow the developments in the field. One of the reasons is that there is a lack of commonly accepted annotated data-sets and standardized evaluation protocols that would allow objective comparison of different tracking methods. To address this issue, the Visual Object Tracking (VOT) workshop was organized in conjunction with ICCV2013. Researchers from academia as well as industry were invited to participate in the first VOT2013 challenge which aimed at single-object visual trackers that do not apply...
The price of anarchy in cooperative network creation games
, Article Leibniz International Proceedings in Informatics, LIPIcs, 26 February 2009 through 28 February 2009 ; Volume 3 , 2009 , Pages 301-312 ; 18688969 (ISSN) ; 9783939897095 (ISBN) ; Hajiaghayi, M ; Mahini, H ; Zadimoghaddam, M ; Sharif University of Technology
Abstract
We analyze the structure of equilibria and the price of anarchy in the family of network creation games considered extensively in the past few years, which attempt to unify the network design and network routing problems by modeling both creation and usage costs. In general, the games are played on a host graph, where each node is a selfish independent agent (player) and each edge has a fixed link creation cost α. Together the agents create a network (a subgraph of the host graph) while selfishly minimizing the link creation costs plus the sum of the distances to all other players (usage cost). In this paper, we pursue two important facets of the network creation game. First, we study...
The mutual impact of demand response programs and renewable energies: a survey
, Article Energies ; Volume 10, Issue 9 , 2017 ; 19961073 (ISSN) ; Ehsan, M ; Soleymani, S ; Shafie Khah, M ; Catalão, J. P. S ; Sharif University of Technology
Abstract
Renewable energies as a solution for environmental issues have always been a key research area due to Demand Response Programs (DRPs). However, the intermittent nature of such energies may cause economic and technological challenges for Independent System Operators (ISOs) besides DRPs, since the acceptable effective solution may exceed the requirement of further investigations. Although, previous studies emphasized employing Demand Response and Renewable Energies in power systems, each problem was investigated independently, and there have been few studies which have investigated these problems simultaneously. In these recent studies, authors neither analyzed these problems simultaneously...
The inapproximability for the (0,1)-additive number
, Article Discrete Mathematics and Theoretical Computer Science ; Volume 17, Issue 3 , 2016 , Pages 217-226 ; 14627264 (ISSN) ; Dehghan, A ; Sharif University of Technology
Discrete Mathematics and Theoretical Computer Science
2016
Abstract
An additive labeling of a graph G is a function H: V(G)→ N, such that for every two adjacent vertices v and u of G, Σw∼v l(w) = Σw∼vl(w) (x ∼ y means that x is joined to y). The additive number of G, denoted by η(G), is the minimum number k such that G has a additive labeling l: V(G)→ Nk. The additive choosability of a graph G, denoted by ηl(G), is the smallest number k such that G has an additive labeling for any assignment of lists of size k to the vertices of G, such that the label of each vertex belongs to its own list. Seamone in his PhD thesis conjectured that for every graph G, η(G) = ηe(G). We give a negative answer to this conjecture and we show that for every k there is a graph G...
The effect of source motion on contaminant distribution in the cleanrooms
, Article Energy and Buildings ; Volume 43, Issue 4 , April , 2011 , Pages 966-970 ; 03787788 (ISSN) ; Sajadi, B ; Molaeimanesh, G. R ; Sharif University of Technology
2011
Abstract
In the recent decades, cleanrooms have found growing applications in broad range of industries such as pharmacy and microelectronics. Concerns about negative effects of the contaminant exposure on the human health and product quality motivate many researchers towards understanding of the airflow and contaminant distribution though these environments. With an improvement in computational capacity of the computers, computational fluid dynamics (CFD) technique has become a powerful tool to study the engineering problems including indoor air quality (IAQ). In this research, indoor airflow in a full-scale cleanroom is investigated numerically using Eulerian-Eulerian approach. To evaluate the...
The combination of CMS with PMC for improving robustness of speech recognition systems
, Article 13th International Computer Society of Iran Computer Conference on Advances in Computer Science and Engineering, CSICC 2008, Kish Island, 9 March 2008 through 11 March 2008 ; Volume 6 CCIS , 2008 , Pages 825-829 ; 18650929 (ISSN); 3540899847 (ISBN); 9783540899846 (ISBN) ; Sameti, H ; Sharif University of Technology
2008
Abstract
This paper addresses the robustness problem of automatic speech recognition systems for real applications in presence of noise. PMCC algorithm is proposed for combining PMC technique with CMS method. The proposed algorithm utilizes the CMS normalization ability in PMC method to takes the advantages of these methods to compensate the effect of both additive and convolutional noises. Also, we have investigated VTLN for speaker normalization and MLLR and MAP for speaker and acoustic adaptation. Different combinations of these methods are used to achieve robustness and making the system usable in real applications. Our evaluations are done on 4 different real noisy tasks on Nevisa recognition...
System-level assertion-based performance verification for embedded systems
, Article 13th International Computer Society of Iran Computer Conference on Advances in Computer Science and Engineering, CSICC 2008, Kish Island, 9 March 2008 through 11 March 2008 ; Volume 6 CCIS , 2008 , Pages 243-250 ; 18650929 (ISSN); 3540899847 (ISBN); 9783540899846 (ISBN) ; Gharehbaghi, A. M ; Hessabi, S ; Sharif University of Technology
2008
Abstract
As contemporary digital systems specifically embedded systems become more and more complex, taking advantage of system-level design is being more widespread. Many embedded systems must operate under strict timing constraints. One of the best methods for examining timing constraints in an embedded system can be done via the performance verification. In this paper an assertion-based verification methodology has been proposed for verifying system-level timing constraints in an embedded system. Performance assertions are specified by an assertion language at the transaction-level of abstraction. A Turing machine and a structure named performance evaluator have been coupled to provide a...
Symmetric bursting behaviors in the generalized FitzHugh-Nagumo model
, Article Biological Cybernetics ; Volume 107, Issue 4 , 2013 , Pages 465-476 ; 03401200 (ISSN) ; Fallah, H ; Razvan, M. R ; Sharif University of Technology
2013
Abstract
In the current paper, we have investigated the generalized FitzHugh-Nagumo model. We have shown that symmetric bursting behaviors of different types could be observed in this model with an appropriate recovery term. A modified version of this system is used to construct bursting activities. Furthermore, we have shown some numerical examples of delayed Hopf bifurcation and canard phenomenon in the symmetric bursting of super-Hopf/homoclinic type near its super-Hopf and homoclinic bifurcations, respectively
Spoken CAPTCHA: a CAPTCHA system for blind users
, Article 2009 Second ISECS International Colloquium on Computing, Communication, Control, and Management, CCCM 2009, Sanya, 8 August 2009 through 9 August 2009 ; Volume 1 , 2009 , Pages 221-224 ; 9781424442461 (ISBN) ; Abolhassani, H ; Sameti, H ; Shirali Shahreza, M. H ; Yangzhou University; Guangdong University of Business Studies; Wuhan Institute of Technology; IEEE SMC TC on Education Technology and Training; IEEE Technology Management Council ; Sharif University of Technology
2009
Abstract
Today, the Internet is used to offer different services to users. Most of these services are designed for human users, but unfortunately some computer programs are designed which abuse these services. CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart) systems are designed to automatically distinguish between human users and computer programs and block such computer programs. Most of current CAPTCHA methods are using visual patterns and hence blind users cannot use them. In this paper, we propose a new CAPTCHA method which is designed for blind people. In this method, a small sound clip is played for the user and he/she is asked to say a word. Then the user...