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    Designing and implementing basic sciences ontology based on concepts and relationships of relevant thesauri

    , Article Iranian Journal of Information Processing Management ; Volume 30, Issue 3 , Nov , 2015 , Pages 677-696 ; 22518223 (ISSN) Hosseini Beheshti, M. S ; Ejei, F ; Sharif University of Technology
    Iranian Research Institute for Scientific Information and Documentation  2015
    Abstract
    Currently, the main portion of knowledge is stored in electronic texts and documents and for transferring that knowledge effectively, we must use proper methods to gather and retrieve relevant information. Ontologies provide means to produce structured documents and use intelligent search instead of keyword search. Ontology defines the common words and concepts used to describe and represent an area of knowledge. However, developing ontologies is a time consuming and labor work. So, many ontology developers try to facilitate and speed up this process by reusing other resources. In fact, thesaurus contains semantic information and hierarchical structure that make it an appropriate resource... 

    Commonsense knowledge extraction for persian language: a combinatory approach

    , Article Iranian Journal of Information Processing Management ; Volume 31, Issue 1 , 2015 , Pages 109-124 ; 22518223 (ISSN) Moradi, M ; Vazirnezhad, B ; Bahrani, M ; Sharif University of Technology
    Iranian Research Institute for Scientific Information and Documentation  2015
    Abstract
    The Putting human commonsense knowledge into computers has always been a long standing dream of artificial intelligence (AI). The cost of several tens of millions of dollars and time have been covered so that the computers could know about "objects falling, not rising.", "running is faster than walking". The large database was built, automated and semi-automated methods were introduced and volunteers' efforts were utilized to achieve this, but an automated, high-throughput and low-noise method for commonsense collection still remains as the holy grail of AI. The aim of this study was to build commonsense knowledge ontology using three approaches namely Hearst method, machine translation and... 

    Combining ontology alignment metrics using the data mining techniques

    , Article 2nd International Workshop on Contexts and Ontologies: Theory, Practice and Applications, C and O 2006 - Collocated with the 17th European Conference on Artificial Intelligence, ECAI 2006, Riva del Garda, 28 August 2006 through 28 August 2006 ; Volume 210 , 2006 ; 16130073 (ISSN) Bagheri Hariri, B ; Sayyadi, H ; Abolhassani, H ; Sheykh Esmaili, K ; Sharif University of Technology
    2006
    Abstract
    Several metrics have been proposed for recognition of relationships between elements of two Ontologies. Many of these methods select a number of such metrics and combine them to extract existing mappings. In this article, we present a method for selection of more effective metrics - based on data mining techniques. Furthermore, by having a set of metrics, we suggest a data-mining-like means for combining them into a better ontology alignment  

    The curious neglect of geometry in modern philosophies of mathematics

    , Article Logic, Epistemology, and the Unity of Science ; Volume 49 , 2021 , Pages 379-389 ; 22149775 (ISSN) Shahshahani, S ; Sharif University of Technology
    Springer Science and Business Media B.V  2021
    Abstract
    From ancient times to 19th century geometry symbolized the essence of mathematical thinking and method, but modern philosophy of mathematics seems to have marginalized the philosophical status of geometry. The roots of this transformation will be sought in the ascendance of logical foundations in place of intuitive primacy as the cornerstone of mathematical certainty in the late 19th century. Nevertheless, geometry and geometrical thinking, in multiple manifestations, have continued to occupy a central place in the practice of mathematics proper. We argue that this, together with advances in the neuroscience of mathematical processes, calls for an expansion of the present limited remit of... 

    Evolutionary coincidence-based ontology mapping extraction

    , Article Expert Systems ; Volume 25, Issue 3 , 2008 , Pages 221-236 ; 02664720 (ISSN) Qazvinian, V ; Abolhassani, H ; Haeri, S. H ; Bagheri Hariri, B ; Sharif University of Technology
    2008
    Abstract
    Ontology matching is a process for selection of a good alignment across entities of two (or more) ontologies. This can be viewed as a two-phase process of (1) applying a similarity measure to find the correspondence of each pair of entities from two ontologies, and (2) extraction of an optimal or near optimal mapping. This paper is focused on the second phase and introduces our evolutionary approach for that. To be able to do so, we need a mechanism to score different possible mappings. Our solution is a weighting mechanism named coincidence-based weighting. A genetic algorithm is then introduced to create better mappings in successive iterations. We will explain how we code a mapping as... 

    On ontology alignment experiments

    , Article Webology ; Volume 3, Issue 3 , 2006 ; 1735188X (ISSN) Abolhassani, H ; Bagheri Hariri, B ; Haeri, S. H ; Sharif University of Technology
    2006
    Abstract
    Ontology Alignment is a process for finding related entities of different ontologies. This paper discusses the results of our research in this area. One of them is a formulation for a new structural measure which extends famous related works. In this measure with a special attention to the transitive properties, it is tried to increase recall with less harm on precision. Second contribution is a new method for compound measure creation without any need to the mapping extraction phase. Effectiveness of these ideas is discussed and quantitative evaluations are explained in this paper. Copyright © 2006, Hassan Abolhassani, Babak Bagheri Hariri, & Seyed H. Haeri  

    Overlapped ontology partitioning based on semantic similarity measures

    , Article 2010 5th International Symposium on Telecommunications, IST 2010, 4 December 2010 through 6 December 2010 ; 2010 , Pages 1013-1018 ; 9781424481835 (ISBN) Etminani, K ; Rezaeian Delui, A ; Naghibzadeh, M ; Sharif University of Technology
    Abstract
    Today, public awareness about the benefits of using ontologies in information processing and the semantic web has increased. Since ontologies are useful in various applications, many large ontologies have been developed so far. But various areas like publication, maintenance, validation, processing, and security policies need further research. One way to better tackle these areas is to partition large ontologies into sub partitions. In this paper, we present a new method to partition large ontologies. For the proposed method, three steps are required: (1) transforming an ontology to a weighted graph, (2) partitioning the graph with an algorithm which recognizes the most important concepts,... 

    Lexical pattern generalization for ontology learning and population: A survey

    , Article Proceedings of the International MultiConference of Engineers and Computer Scientists 2010, IMECS 2010, 17 March 2010 through 19 March 2010 ; 2010 , Pages 551-554 ; 9789881701282 (ISBN) Rastegari, Y ; Sayadiharikandeh, M ; Zibanezhad, B ; Sharif University of Technology
    Abstract
    Information extraction and refinement systems rely on a set of extraction patterns in pattern based approaches in order to construct taxonomies and finding instances of concepts in a corpus. Pattern based methods have high precision and suffer from low recall. Pattern generalization and modeling techniques can increase matching power and decrease GAP between training and test data  

    Collecting positive instances of "instance-of" relationship in the Persian language

    , Article ICECT 2010 - Proceedings of the 2010 2nd International Conference on Electronic Computer Technology, 7 May 2010 through 10 May 2010, Kuala Lumpur ; May , 2010 , Pages 46-49 ; 9781424474059 (ISBN) Rastegari, Y ; Abolhassani, H ; Zibanezhad, B ; Sayadiharikandeh, M ; Sharif University of Technology
    2010
    Abstract
    Fetching Lexico-Syntactic patterns from text rely on pairs of words (positive instances) that represent the target relation, and finding their simultaneous occurrence in text corpus. Due to existence of WordNet thesaurus (which contains the semantic relationship between words), collecting positive instances is easy. In non-english languages, it's hard to collect large number of positive instances in various contexts. We investigated some new ideas for collecting them in Persian language and finally run the best one and collected approximately 6,000 positive instances  

    Automatic extraction of is-a relations in taxonomy learning

    , 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 17-24 ; 18650929 (ISSN); 3540899847 (ISBN); 9783540899846 (ISBN) Neshati, M ; Abolhassani, H ; Fatemi, H ; Sharif University of Technology
    2008
    Abstract
    Taxonomy learning is a prerequisite step for ontology learning. In order to create a taxonomy, first of all, existing 'is-a' relations between words should be extracted. A known way to extract 'is-a' relations is finding lexicosyntactic patterns in large text corpus. Although this approach produces results with high precision but it suffers from low values of recall. Furthermore developing a comprehensive set of patterns is tedious and cumbersome. In this paper, firstly, we introduce an approach for developing lexico-syntactic patterns automatically using the snippets of search engine results and then, challenge the law recall of this approach using a combined model, which is based on... 

    Study and Improvement of a Model for Context-Aware Semantic Web Services

    , M.Sc. Thesis Sharif University of Technology Keivanloo, Iman (Author) ; Abolhassani, Hassan (Supervisor)
    Abstract
    Web service plays an important role in software development. Since Web service can be used in small scale and large scale environments, many different entities may participate in each interaction. Regarding situation, a lot of information is available around these entities. This kind of information is called context. In some cases, context information is used to provide outputs which are called context-aware systems.
    The main challenging issue in producing a context-aware system is context modeling and sharing. Semantic Web and its ontology languages are the most promising solution to context modeling. In pervasive computing many ontologies are proposed for this purpose, but little... 

    Handling context in a semantic-based access control framework

    , Article Proceedings - International Conference on Advanced Information Networking and Applications, AINA, 26 May 2009 through 29 May 2009, Bradford ; 2009 , Pages 103-108 ; 1550445X (ISSN); 9780769536392 (ISBN) Ehsan, M. A ; Amini, M ; Jalili, R ; IEEE Computer Society ; Sharif University of Technology
    2009
    Abstract
    As semantic web grows, security concerns increase. One concern is controlling accesses to resources in this environment. In order to infer whether the access is allowed or not, different information of different entities including contextual information should be involved. From access control point of view, we divide the entities in semantic web into three categories: resources (objects), requesters (subjects), and environment (infrastructure, time, and location). In this paper, we present a semantic-based context-aware access control framework to be applied in semantic web, considered as a multi-domain environment. To handle context information in the framework, we propose a context... 

    Using background knowledge and context knowledge in ontology mapping

    , Article Frontiers in Artificial Intelligence and Applications ; Volume 174, Issue 1 , 2008 , Pages 56-64 ; 09226389 (ISSN); 9781586038717 (ISBN) Fatemi, H ; Sayyadi, M ; Abolhassani, H ; Sharif University of Technology
    IOS Press  2008
    Abstract
    Recent evaluations of mapping systems show that lack of background knowledge, most often domain specific knowledge, is one of the key problems of mapping systems these days. In fact, at present, most state of the art systems, for the tasks of mapping large ontologies, perform not with such high values of recall (~ 30%), because they mainly rely on label and structure based similarity measures. Disregarding context knowledge in ontology mapping is another drawback that almost all current approaches suffer from. In this paper we use the semantic web as background knowledge and introduce a novel approach for capturing context knowledge from the ontology for improving mapping results. We have... 

    Coincidence based mapping extraction with genetic algorithms

    , Article 3rd International Conference on Web Information Systems and Technologies, Webist 2007, Barcelona, 3 March 2007 through 6 March 2007 ; Volume WIA , 2007 , Pages 176-183 Qazvinian, V ; Abolhassani, H ; Haeri, S. H ; Sharif University of Technology
    2007
    Abstract
    Ontology Aligning is an answer to the problem of handling heterogenous information on different domains. After application of some measures, one reaches a set of similarity values. The final goal is to extract mappings. Our contribution is to introduce a new genetic algorithm (GA) based extraction method. The GA, employs a structured based weighting model, named "coincidence based model", as its fitness function. In the first part of the paper, some preliminaries and notations are given and then we introduce the coincidence based weighting. In the second part the paper discusses the details of the devised GA with the evaluation results for a sample dataset  

    Proposing a new Approach for Ontology Alignment Based on Graphcoincidence

    , M.Sc. Thesis Sharif University of Technology Ghanbarpour, Asieh (Author) ; Abolhassani, Hassan (Supervisor)
    Abstract
    An ontology is a formal description of a domain by definition a set of concepts and the relationships between those concepts. Ontologies defined by different applications usually describe their domains in different terminologies,even when they cover the same domain. Thus, we need to resolve the semantic heterogeneities problem and align terms in different ontologies. Ontology alignment plays the central role in these areas to identify correspondences among elements of two or more ontologies. It should be noted that,finding an optimize mapping between two ontologies with respect to search space is an NP-hard [6] problem.
    In This thesis we focused on large ontologies and alignment among... 

    Commonsense knowledge Extraction for Persian Language:A Combinatory Approach

    , M.Sc. Thesis Sharif University of Technology Moradi, Mehdi (Author) ; Vazirnezhad, Bahram (Supervisor) ; Bahrani, Mohammad (Co-Advisor)
    Abstract
    Putting human commonsense knowledge into computers has always been a long standing dream of artificial intelligence (AI). Since the first days of its appearance, AI knowledge engineers were studying hard to get round this bottleneck. The cost of several tens of millions of dollars and times have been covered so that the computers could know about “objects falling, not rising.”,” running is faster than walking" And “death is the end of the life”. The large database was built, automated and semi-automated methods were introduced and volunteers’ efforts were utilized to achieve this, but an automated, high-throughput and low-noise method for commonsense collection still remains as the holy... 

    Analysis of Bruno Latour’s Metaphysics and Realism

    , M.Sc. Thesis Sharif University of Technology Farokhi Kakesh, Hadis (Author) ; Taghavi, Mostafa (Supervisor)
    Abstract
    Bruno Latour is one of the well-known contemporary philosophers in the field of science and technology studies. He is specially famouse for his work in laboratory studies and also for rejecting the dualities of modernity. By rejecting subject/object division, Latour opens new perpectives in Ontology. Ontology is one of the most important contributions of Latour to philosophy. He is also one of the primary developers of actor-network theory.In this research, I elaborate on ontological ideas of Latour. First, I will clarify his position in regard to modernity and show how he withdraws from dualities of modernity. Then I will explain his ontological pluralism. Based on this approach, I will... 

    Semantic data gathering of physical entities in semantic sensor networks using software agents

    , Article Information Technology and Control ; Volume 47, Issue 2 , 2018 , Pages 167-183 ; 1392124X (ISSN) Ahmadinia, M ; Movaghar, A ; Rahmani, A. M ; Sharif University of Technology
    Kauno Technologijos Universitetas  2018
    Abstract
    In a wireless sensor network, with numerous sensor nodes, a huge volume of data is produced. For the massive data generated by sensor networks to be understood by the machine, semantic web technologies such as ontology need to be applied. On the other hand, since the end users intend to access the high-level physical entities information monitored by the sensor network, the applicability of sensor networks can be enhanced through proposing a strategy to extract the data based on entities instead of extracting the raw sensor data. Hence, in this paper firstly, ontology will be presented for physical entities semantic modelling (PESM). Secondly, an appropriate strategy will be offered to... 

    Knowledge active forgetting: the forgotten side of knowledge management

    , Article PICMET 2009 - 2009 Portland International Conference on Management of Engineering and Technology, Portland, OR, 2 August 2009 through 6 August ; 2009 , Pages 1007-1018 ; 1890843202 (ISBN); 9781890843205 (ISBN) Rezazade Mehrizi, M. H ; Bagherzadeh Niri, M ; Rahimi, M ; Yarmand, H ; Sharif University of Technology
    2009
    Abstract
    As Gregory Bateson, the British social scientists, once said "You can't live without an eraser", the process of learning is not a unidirectional way toward accumulation of knowledge, rather, organizations should critically evaluate the value of their knowledge and if necessary, actively forget no-longer-useful knowledge. A brief review of related literature shows that the concept of knowledge active forgetting (KAF) is a crucial aspect of organizational learning and knowledge management. However, many aspects of this topic deserve more attention by researchers. The main gap in the literature seems to be related to the linkage between peculiar aspects of knowledge (such as stickiness, context... 

    Taxonomy construction using compound similarity measure

    , Article OTM Confederated International Conferences CoopIS, DOA, ODBASE, GADA, and IS 2007, Vilamoura, 25 November 2007 through 30 November 2007 ; Volume 4803 LNCS, Issue PART 1 , 2007 , Pages 915-932 ; 03029743 (ISSN); 9783540768463 (ISBN) Neshati, M ; Hassanabadi, L. S ; Sharif University of Technology
    Springer Verlag  2007
    Abstract
    Taxonomy learning is one of the major steps in ontology learning process. Manual construction of taxonomies is a time-consuming and cumbersome task. Recently many researchers have focused on automatic taxonomy learning, but still quality of generated taxonomies is not satisfactory. In this paper we have proposed a new compound similarity measure. This measure is based on both knowledge poor and knowledge rich approaches to find word similarity. We also used Neural Network model for combination of several similarity methods. We have compared our method with simple syntactic similarity measure. Our measure considerably improves the precision and recall of automatic generated taxonomies. ©...