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    A model-driven approach to semi-structured database design

    , Article Frontiers of Computer Science ; Volume 9, Issue 2 , 2015 , Pages 237-252 ; 20952228 (ISSN) Jahangard Rafsanjani, A ; Mirian Hosseinabadi, S ; Sharif University of Technology
    Higher Education Press  2015
    Abstract
    Recently XML has become a standard for data representation and the preferred method of encoding structured data for exchange over the Internet. Moreover it is frequently used as a logical format to store structured and semi-structured data in databases. We propose a model-driven and configurable approach for modeling hierarchical XML data using object role modeling (ORM) as a flat conceptual model. First a non-hierarchical conceptual schema of the problem domain is built using ORM and then different hierarchical views of the conceptual schema or parts of it are specified by the designer using transformation rules. A hierarchical modeling notation called H-ORM is proposed to show these... 

    Lightweight formalization and validation of ORM models

    , Article Journal of Logical and Algebraic Methods in Programming ; Volume 84, Issue 4 , July , 2015 , Pages 534-549 ; 23522216 (ISSN) Jahangard Rafsanjani, A ; Mirian Hosseinabadi, S. H ; Sharif University of Technology
    Elsevier Inc  2015
    Abstract
    Abstract ORM (Object Role Modeling) is a rich and popular conceptual modeling method. ORM has been used for data modeling, ontology engineering, modeling business rules, XML-Schemes and data warehouses, requirements engineering and web forms. Automated reasoning like satisfiability testing allows developers to detect modeling mistakes in the early stages of development. In this paper we propose a lightweight formalization of the ORM meta-model in Alloy. Using this meta-model as a toolkit one can easily specify ORM models in Alloy and verify various properties on them using the Alloy Analyzer. In order to achieve scalability, we use the cardinality of concepts to model their population. This... 

    A top down approach to semi-structured database design

    , Article 2nd International Conference on the Applications of Digital Information and Web Technologies, ICADIWT 2009 ; 2009 , Pages 26-31 ; 9781424444571 (ISBN) Jahangard Rafsanjani, A ; Mirian Hosseinabadi, S. H ; Sharif University of Technology
    2009
    Abstract
    XML has become the preferred format for representing and exchanging structured and semi-structured data on the web. The XML Schema language is widely used for defining and validating highly structured XML instance documents. While text-based languages, such as XML-Schema, offer great advantages for data interchange on the Internet, graphical modeling languages are widely accepted as a more visually effective means of specifying and communicating data requirements for a human audience. This paper uses Object-Relationship-Attribute model (ORA-SS) as a conceptual graphical model for designing XML-Schemas. To facilitate this process we introduce an xml representation for ORA-SS Schema Diagram... 

    A Z approach to formalization and validation of ORM models

    , Article Communications in Computer and Information Science, 20 July 2011 through 22 July 2011 ; Volume 194 CCIS , July , 2011 , Pages 513-526 ; 18650929 (ISSN) ; 9783642226021 (ISBN) Jahangard Rafsanjani, A ; Mirian Hosseinabadi, S. H ; Springer ; Sharif University of Technology
    2011
    Abstract
    In this paper we present a formal definition of the basic concepts and notations of Object Role Modeling (ORM) using the Z formal specification language. Most of ORM concepts such as object and relationship types, value types, objectification, reference schemes, sub-types, roles and constraints such as uniqueness, mandatory, cardinality, subset, equality, exclusive and ring constraints are specified formally. Population is specified as objects, relationships and roles instances. These are specified using Z axioms and diagram instances are specified using Z schemas. This would enable validation and reasoning on the formal properties of ORM diagrams such as detecting constraint contradictions... 

    A Unified Approach to Modeling and Design of Semi-structured Databases

    , Ph.D. Dissertation Sharif University of Technology Jahangard Rafsanjani, Amir (Author) ; Mirian Hosseinabadi, Hassan (Supervisor)
    Abstract
    Recently XML has become a standard for data representation and the preferred method of encoding structured data for exchange over the Internet. Moreover it is frequently used as a logical format to store structured and semi-structured data in databases. In this research we focus on semantic modeling for XML data and we propose a model-driven approach for modeling and designing XML databases. In the approach data is modeled without considering representation and implementation details in a platform independent model.
    We use Object-Role Modeling as the platform independent model. We specify a formal meta-model of this model in Alloy and we validate instance models by checking... 

    Identifying monitoring nodes in MANET by detecting unauthorized and malicious nodes

    , Article International Symposium on Information Technology 2008, ITSim, Kuala Lumpur, 26 August 2008 through 29 August 2008 ; Volume 3 , 2008 ; 9781424423286 (ISBN) Kuchaki Rafsanjani, M ; Movaghar, A ; Sharif University of Technology
    2008
    Abstract
    Mobile ad hoc networks have different characteristics from wired networks. There are new challenges related to security issues that need to be addressed. In this paper, first, critical nodes and authentication in mobile ad hoc networks are discussed. Then, a monitoring nodes selection method with high battery power in these networks is presented. We propose a three-phase detection scheme. In the first phase, unauthorized nodes and in the second phase, malicious nodes are detected. Finally in the third phase, nodes with the largest battery power as monitoring nodes are considered. In the first and the second phases, detection scheme uses non-interactive zero knowledge technique in order to... 

    An efficient method for identifying IDS agent nodes by discovering compromised nodes in MANET

    , Article 2009 International Conference on Computer and Electrical Engineering, ICCEE 2009, 28 December 2009 through 30 December 2009, Dubai ; Volume 1 , 2009 , Pages 625-629 ; 9780769539256 (ISBN) Kuchaki Rafsanjani, M ; Khavasi, A. A ; Movaghar, A ; Sharif University of Technology
    2009
    Abstract
    Intrusion Detection Systems (IDS) for Mobile Ad hoc NETworks (MANETs) are necessary when they are deployed in reality. In This paper, we have presented a combined method of selecting IDS agent nodes in mobile ad hoc networks. Since, the IDS agents in MANET due to more activities need to more battery power. In our method, first, compromised nodes are detected and then the nodes with the highest energy power from among valid nodes as IDS agent nodes are considered. So, with this method, some valid nodes contribute in intrusion detection activities and costs of the network monitoring will be reduced and the network lifetime will be increased. © 2009 IEEE  

    An effective approach for determining IDS agent nodes in manet

    , Article Proceedings of the 3rd International Conference on Internet Technologies and Applications, ITA 09, 8 September 2009 through 11 September 2009, Wrexham, Wales ; 2009 , Pages 458-465 ; 9780946881659 (ISBN) Kuchaki Rafsanjani, M ; Khavasi, A. A ; Movaghar, A ; Sharif University of Technology
    2009
    Abstract
    Mobile Ad hoc NETworks (MANET) due to different characteristics from wired networks are more vulnerable to security attacks. Construction of Intrusion Detection Systems (IDS) for MANETs is complicated by the fact that they are lack of fixed infrastructure and lack of central management for authentication and distribution of cryptographic keys. On the other hand, the network lifetime is an important issue in MANETs because of the energy power of mobile nodes is limited. In this paper is presented a proposed Method that in the first step, authorized nodes are detected by non-interactive zero knowledge technique and in the second step, nodes with the highest battery power from among authorized... 

    Frequency response calculation of non-linear torsional vibration in gear systems

    , Article Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics ; Volume 222, Issue 1 , 2008 , Pages 49-60 ; 14644193 (ISSN) Farshidianfar, A ; Moeenfard, H ; Rafsanjani, A ; Sharif University of Technology
    2008
    Abstract
    The current paper focuses on the non-linear torsional vibration of a one-stage transmission gear system. Four different methods have been applied for solution of the equation of motion; the discretization method, the perturbation method, the Ritz method, and the stepwise time integration of the equation of motion. The time and frequency results from these analyses have been compared with each other, as well as those reported in literatures. Although all of these methods are accurate and computationally effective for finding the main spectral contribution, however, only the discretization method and the step-wise time-integration model are able to identify the other frequency components. ©... 

    RIAL: Redundancy reducing inlining algorithm to map XML DTD to relations

    , Article 2008 International Conference on Computational Intelligence for Modelling Control and Automation, CIMCA 2008, Vienna, 10 December 2008 through 12 December 2008 ; July , 2008 , Pages 25-30 ; 9780769535142 (ISBN) Rafsanjani, A. J ; Mirian Hosseinabadi, S. H ; Sharif University of Technology
    2008
    Abstract
    XML has emerged as a common standard for data exchange over the World Wide Web. One way to manage XML data is to use the power of relational databases for storing and querying them. So the hierarchical XML data should be mapped into flat relational structure. In this paper we propose an algorithm which maps DTD to relational schema and as well as content and structure it preserves the functional dependencies during the mapping process in order to produce relations with less redundancy. This is done by categorizing functional dependencies and introducing four rules to be applied to the relations created by the hybrid inlining algorithm according to each category. These rules will reduce... 

    Nonlinear dynamic modeling of surface defects in rolling element bearing systems

    , Article Journal of Sound and Vibration ; Volume 319, Issue 3-5 , 2009 , Pages 1150-1174 ; 0022460X (ISSN) Rafsanjani, A ; Abbasion, S ; Farshidianfar, A ; Moeenfard, H ; Sharif University of Technology
    2009
    Abstract
    In this paper an analytical model is proposed to study the nonlinear dynamic behavior of rolling element bearing systems including surface defects. Various surface defects due to local imperfections on raceways and rolling elements are introduced to the proposed model. The contact force of each rolling element described according to nonlinear Hertzian contact deformation and the effect of internal radial clearance has been taken into account. Mathematical expressions were derived for inner race, outer race and rolling element local defects. To overcome the strong nonlinearity of the governing equations of motion, a modified Newmark time integration technique was used to solve the equations... 

    Predictive tri-linear benchmark curve for in-plane behavior of adobe walls

    , Article International Journal of Architectural Heritage ; Volume 9, Issue 8 , Nov , 2015 , Pages 986-1004 ; 15583058 (ISSN) Rafsanjani, S. H ; Bakhshi, A ; Ghannad, M. A ; Yekrangnia, M ; Soumi, F ; Sharif University of Technology
    Taylor and Francis Inc  2015
    Abstract
    In the present study, numerical simulations are conducted to estimate the in-plane response of adobe walls subjected to pseudo-static cyclic loading based on the finite element code ABAQUS. The simplified micro-modeling approach is adopted and an interface model reported in ABAQUS material library is applied as material model for zero-thickness interface elements. The comparison between obtained results and field test data results in good agreement. Parametric studies are carried out to evaluate the effectiveness of independent parameters changes on response of adobe walls. It is noted that mechanical properties of joints and adobe units play an active role on in-plane behavior of walls. A... 

    From-Focused Second Language Vocabulary Learning: A Case for Translation and Dictionary Search

    , M.Sc. Thesis Sharif University of Technology Akbari, Somayeh (Author) ; Jahangard, Ali (Supervisor)
    Abstract
    The purpose of the study was four-fold: first to investigate the predictive adequacy of the Task-Induced Involvement Load Hypothesis which contends that higher-load inducing tasks yield better retention rates in incidental learning situations, second, to examine whether type of dictionary search could affect vocabulary retention, third, to investigate the effect of translation direction on retention rate, and finally to determine the most effective tasks. To meet these ends, six groups of EFL learners - all male, aging 19-25, majoring in various fields of engineering sciences were assigned to the study. Each one of the groups performed distinct tasks which were as follow: reading... 

    Curriculum Evaluation: Analysis of Teachers' and Students' Attitudes toward EFL Textbook Series

    , M.Sc. Thesis Sharif University of Technology Alani, Amin (Author) ; Jahangard, Ali (Supervisor)
    Abstract
    According to Sheldon (1988) textbooks are visible hearts of any English language teaching program. Relevant textbooks are prerequisites of an appropriate teaching and learning situation (Hutchinson & Torres, 1994). Evaluation is helpful for making subsequent informed decisions through providing information on the usefulness and effectiveness of textbooks (Allwright, 1981). The Right Path to English and English Book are two Iranian textbook series that have been prescribed by the Ministry of Education for teaching in public Junior and Senior high schools, respectively. Employing Litz's (2005) questionnaires, attitudes of Iranian learners and teachers were obtained on both the series.... 

    A Comparison of Three Vocabulary Teaching Methods: A Case for Task/Test Compatibility

    , M.Sc. Thesis Sharif University of Technology Shamsi, Yaser (Author) ; Jahangard, Ali (Supervisor)
    Abstract
    The importance of vocabulary, the building blocks of every language, in having a good command of a second language is evident. However, the best way to improve the lexical knowledge of the students is an issue that is open to discussions. This study aimed at investigating three different methods for teaching new vocabularies to Iranian students who were striving to take command of English as a second language in order to determine the advantages of one method over the other in terms of immediate and delayed retention. In this endeavor, we set 105 intermediate adult learners of English into three groups and instructed each group with a specific method, teaching them a number of new words... 

    An Evaluation of an Iranian Secondary School EFL Textbook: A Teachers’ and Learners’ Attitude Study

    , M.Sc. Thesis Sharif University of Technology Bemani, Mohsen (Author) ; Jahangard, Ali (Supervisor)
    Abstract
    Textbooks play major roles in education and incorporation of textbooks into the courses can better the outcome of the learning (McGrath, 2006; Sheldon, 1988). Considering the role of textbooks, it seems crucial to examine and evaluate textbooks to select the best material for the educational courses (Tomlinson, 2001). This study focused on the evaluation of the EFL textbook, Prospect 1, which is currently taught at secondary schools of Iran. The researcher intended to evaluate the textbook from the perspectives of both teachers and learners based on the evaluation model proposed by Litz (2005). The participants of the study were 173 learners and 102 teachers who filled out the questionnaires... 

    The Effect of Learner-Centered Blogging on the Iranian Students’ Essay Writing Skill and Attitude

    , M.Sc. Thesis Sharif University of Technology Heydari, Afsaneh (Author) ; Jahangard, Ali (Supervisor)
    Abstract
    Computer-assisted language learning (CALL) has been the focus of investigation in the field of foreign language learning for many years. This study aimed to investigate the impact of learning through blogging on the students’ essay writing skill and attitude in the Iranian context. As an extension of the research conducted earlier by Lin (2015) 32 Sharif University of Technology students were selected as the participants of the study. To this end, the students were divided into two groups of experimental group and control group. Then, they were instructed in two different ways by using different teaching methodologies. The bloggers, experimental group students, did not receive any direct... 

    A Mixed-Method Investigation into the Effects of Planning Conditions on EFL Writing Quality: Learners’ Planning Strategies and Point of View Adoption under the Spot Light

    , M.Sc. Thesis Sharif University of Technology Aaj, Foozieh (Author) ; Jahangard, Ali (Supervisor)
    Abstract
    Adopting a mixed-methods research approach, this study investigated the impacts of four task planning conditions, i.e. online planning (OLP), pre-task planning (PTP), combined pre-task planning and online planning (PTP+OLP), and no planning (NP) on written narrative output which was elicited by means of a picture composition from 80 female advanced EFL learners. The narratives were analyzed in terms of complexity, accuracy, and fluency (CAF). Moreover, in the qualitative part of this study, how learners planned during pre-task planning time and the content of their narratives were analyzed. The results of the one-way ANOVAs showed that the PTP+OLP group produced significantly more complex,... 

    The Effectiveness of Mnemonic Devices, Visualization and Pictorial Techniques on Vocabulary Learning Process

    , M.Sc. Thesis Sharif University of Technology Moghadas, Behrouz (Author) ; Jahangard, Ali (Supervisor)
    Abstract
    The importance of having a rich repertoire of vocabulary at one’s disposal is evidently an undeniable fact for a successful communication. However, the best way to improve the lexical knowledge of the students is an issue that is still open to dispute. Considering this issue the present study focused on vocabulary learning strategies in L2 teaching. Actually, this study aimed at investigating three different methods of teaching new words to Iranian students in order to determine which one of the methods is more effective in terms of immediate and delayed retention. So the researchers strived to examine the question of how two different mnemonic devices, i.e., the Keyword method and the... 

    Partial Vocabulary Learning through Multimedia Input: An Analysis of the Effects of Captions and Subtitles

    , M.Sc. Thesis Sharif University of Technology Soltani, Mohammad (Author) ; Jahangard, Ali (Supervisor)
    Abstract
    The current study aimed to investigate the differential effects of multimedia input with no subtitle, subtitle, or caption (L2 subtitle) on vocabulary retention while controlling for the possible effects of students' vocabulary size and language aptitude as covariates. A total of 81 undergraduate university students were assigned to the study from three intact groups at Sharif University of Technology. All of the participants were Persian speakers and were in the age range of 18 and 22 years old; homogeneity of the students regarding their language proficiency was also established. During two different sessions, students' vocabulary size and language aptitude were measured. The groups were...