Ontology Based Information Retrieval for E-Tourism

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					                                                        (IJCSIS) International Journal of Computer Science and Information Security,
                                                        Vol. 8, No. 2, May 2010




           Ontology Based Information Retrieval for
                                                    E-Tourism
          G.Sudha Sadasivam                             C.Kavitha                                           M.SaravanaPriya
        Professor,Department of CSE                     Senior Lecturer                       PG Student
        PSG College of Technology                       PSG College of Technology             PSG College of Technology
        Coimbatore,India                                Coimbatore, India                     Coimbatore, India
   Email id: sudhasadhasivam@yahoo.com                  Email id:mail2kavithak@yahoo.com Email id:priyakut@gmail.com



Abstract - This paper reports work done in the E-Tourism                  agents to analyze the Web on our behalf, making smart
project. The overall goal of the project is to improve information        inferences that go beyond the simple linguistic analysis
creation, maintenance and delivery in the tourism industry by             performed by today’s search engines [5]. The applications that
introducing semantic technologies. This paper analyzes the                deliver these new online solutions are based on ontology.
weakness of keyword based techniques and proposes need for
                                                                          Ontology is basically a description of the key concepts in a
semantic based intelligent information retrieval for tourism
domain. The Semantic Web is an evolving development of the                given domain including the rules, properties and relationships
World Wide Web in which the meaning of information and                    between concepts. There are many challenges involved in
services on the web is defined, making it possible for the web to         implementing such an innovative new approach for online
understand and satisfy the requests of people and machines to             search services. Ontology modeling and ontology based
use the web content. It also supports the transparent exchange of         information retrieval are two of the major issues faced by
information and knowledge among collaborating e-business                  developers. In this paper, Ontology modeling tool Protégé and
organizations. It focuses meaningful exchange of knowledge                an architecture based on the tool aimed at addressing these
between organizations. Major challenge faced by the semantic              issues are presented. The paper proposes a convenient and
web application is modeling of ontology and ontology based
                                                                          effective way for ontology engineer to create domain ontology
information retrieval. The software framework has been
developed using Protégé tool for Travels and Tourism domain.              enables Ontology engineer to update the ontology by adding
This framework facilitates creation and maintenance of ontology.          instances and deploys effective applications and facilitates
The paper also proposes two methods for information retrieval             ontology based querying of Semantic Web resources.
namely top down and bottom up approach. A comparison of
these two approaches also presented in the paper.                                         II. PROPOSED ARCHITECTURE
Keywords: Semantic Web, Keyword based Search Engine,                           Fig 1 represents a framework to support convenient and
Ontology, Protégé Tool, Jambalaya, Jena Agent.                            intelligent querying of Semantic Web resources for
                                                                          information retrieval. The key role players of this architecture
                                                                          include Admin, Ontology modeling tool Protégé and End user.
                       I. INTRODUCTION
                                                                               A. Design Steps
          When surfing on the Internet, end users are                     1. The admin or ontology engineer creates ontology by using
increasingly in need of more powerful tools capable of                    protégé tool.
searching and interpreting the vast amount of heterogeneous               2. If any new activity is to be added to the ontology, the
information available on the Web. Current Web has been                    ontology needs to be updated. The ontology engineer updates
designed for direct human processing, but the next-generation             the ontology by adding instances.
“Semantic     Web,” aims        at    machine-process      able           3. End user searches for web content in the same way as in a
information[8].The Semantic Web also provides the                         conventional search engine and issues requests using the
foundation for semantic architecture to support the transparent           system’s GUI
exchange of information and knowledge among collaborating                 4. The End users query to Jena agent and ontology will be
e-business organizations [2]. Recent advances in the Semantic             traversed either top down or bottom up approach according to
Web technologies offer means for organizations to exchange                end user specification
knowledge in a meaningful way [5]. The idea allows software               5. The Jena agent retrieves the query result and passes the
                                                                          result to GUI.




                                                                     78                                 http://sites.google.com/site/ijcsis/
                                                                                                        ISSN 1947-5500
                                                               (IJCSIS) International Journal of Computer Science and Information Security,
                                                               Vol. 8, No. 2, May 2010




  6. The GUI displays the results to the end user.                           end user selects the source name, destination name and
                                                                             budget, then ontology will be traversed and meaningful result
                                                                             will be displayed based on top down approach. If the end user
                                                                             Specifies the restaurant name, accommodation name and
                                                                             travels name then ontology will be traversed using bottom up
                              Jena Agent
                                                                             approach
                              Protégé tool
                                                                                             IV IMPLEMENTATION DETAILS

Admin                                                                                 Protégé is used to model ontology. It is an open
              Ontology                         Ontology                      source tool which is used to construct knowledge based
              Creation                         updation                      application using ontology. Ontology is a formal explicit
                                                                             specification of shared conceptualization. It provides a
                                                                             platform for ontology engineers to create ontology and form
                                                                             the ontology knowledge-base. The tool displays and edits
                                                                             ontology in graphical mode, and can synchronously create
                                Ontology                                     ontology OWL [6] files as well. The work of creating
                                                                             ontology is realized by jambalya[9], Property Window,
                                                                             Individual Editor Window. According to the outline view, all
                                                                             the ontology objects and relative properties could be listed and
                                                                             displayed. The multi-layer edit view comprises two parts
                          Ontology Traversal
                                                                             namely Class edit view and Property edit view. The edit view
                                                                             displays subclasses, instances, classes, inheritance and
                                                                             equivalence, mapping relation between class and instance .The
                                                                             edit view of Property displays properties, inheritance and
                                                                             equivalence relation of properties

                                                                              A. Tourism Domain Ontology Creation:

                                                                                         The Protégé tool is used to create Travels and
                  Query                               Result
                                                                             Tourism domain ontology. Fig.2 displays Travels and Tourism
                                                                             domain ontology created by Protégé tool using Jambalya. It
                                                                             has travels and tourism ontology with Travels, Restaurant,
End-User
                                                                             Accommodation, and Activity concepts for the cities like
                                                                             Mumbai, Chennai, Delhi, Hyderabad, Kolkata and Bangalore.
                                                                             Properties and relationship are set between each concept.
                                                                             Instance is created for each concept and value is assigned for
                         Fig. 1 System Architecture
                                                                             each instance. Class Editor Window enables the ontology
                                                                             engineer to create and update the classes. Multiple siblings can
                                                                             be created for a same class. Based on the need, the ontology
                  III PROPOSED METHODOLOGY                                   engineer can set the restrictions and comment for each classes.
                                                                             The ontology engineer can create a number of properties for a
        A. Travels and Tourism                                               class using property window. Property window includes two
                                                                             types of properties namely Data type property, Object
       The Travels and Tourism Recommendation System is a                    property. The data type property mentions the data type for
  travel consultancy system designed to provide budget                       each property. The ontology engineer has to specify property
  traveling details to customer. Although travel resources on the            with corresponding subclass, range and allowable values for
  internet are abundant, information is widely distributed among             that property. The object poperty mentions the relationship
  multiple travel agents. If end users want to gather information,           between each class or concept. In the edit view of Property
  they need to spend time searching on the internet. The results             window, properties, inheritance and equivalence relation of
  of the query are usually not accurate and sufficient. So it is             properties are all displayed here. The ontology engineer
  necessary to design Travels and Tourism Recommendation                     creates number of instances or individuals for each class or
  System to help budget travelers to arrange their journey and               concept and assign values for each instance based on data
  budget [6]. In Tourism recommendation system, whenever the                 type property.




                                                                        79                                 http://sites.google.com/site/ijcsis/
                                                                                                           ISSN 1947-5500
                                                     (IJCSIS) International Journal of Computer Science and Information Security,
                                                     Vol. 8, No. 2, May 2010




                                                                                     C. Searching and Retrieval

                                                       In                  In Travels and Tourism Recommendation system, when
                                                                    the end user issues requests the ontology will be traversed
                                                                    using top down approach or bottom up approach

                                                       , when .        1) Top down Approach:

                                                                             In this approach the end user has to specify the
                                                                    source name, destination name and budget, according to
                                                                    budget the ontology will be traversed and results will be
                                                                    displayed to end user. It has 2 choices namely travel agency
                                                                    choice and enduser choice.

                                                                             a) Travel Agency Choice: Here the end user specifies
                                                                    the source name, destination name and budget. The Travel
                                                                    agency queries the end user for his preference namely Travels
                                                                    or Tourism. If end user preference namely travels then details
                                                                    of luxury travels are extracted. If the end user preference is
                                                                    tourism details of tourist spots are extracted. According to end
                                                                    users budget, travels and tourism ontology instance weight
               Fig. 2 Travels and Tourism Ontology                  will be added. The sum of instance weight is which is less than
                                                                    or equal to end user budget as results will be extracted and
           B. Tourism Domain Ontology Updation
                                                                    displayed.
         The ontology engineer can update the ontology by
adding instances.




                                                                                        Fig. 4 Travel Agency choice


                                                                       Fig 4 displays the searching result based on budget
                 Fig. 2 Ontology updation                              estimation, preference and distance between source and
                                                                       destination. According to end user estimation and
Fig.3 displays the ontology updation dynamically during run
                                                                       preference, the corresponding destination Tourist spots,
time. The ontology engineer has to specify the instance name
                                                                       Restaurant,        Accommodation and Travels details are
with corresponding concept name to which instance is to be
                                                                       displayed based on sum of instance weight.
dynamically added. Finally ontology gets updated




                                                               80                                  http://sites.google.com/site/ijcsis/
                                                                                                   ISSN 1947-5500
                                                     (IJCSIS) International Journal of Computer Science and Information Security,
                                                     Vol. 8, No. 2, May 2010




          b) End User Choice: End users are also provided
  with facilities to look over travels and tour spots. The end
  users favorite’s travel, accommodation, restaurant, and tour
  spot and wishes to visit it in future, can be marked as his
  favorite spots. Fig 5 displays the information retrieval
  according to end user specification. The end user has to
  specify source name, destination name and budget category.
  According to budget category (luxury or medium or
  ordinary) the tourist spot, accommodation, restaurant and
  travels details are extracted.




                                                                                   Fig. 6 Bottom up with travel agency choice

                                                                                b) End User Choice:     The Fig 7 displays bottom up
                                                                      traversal with end user choice.   Once the end user is provided
                                                                      with all the instances based on   his choice the system displays
                                                                      destination, type and category    of restaurant, accommodation
                                                                      and travels.




                     Fig. 5 End User choice


        2) Bottom up approach:

      The bottom up approach is used to identify the location
and category of specified activity, accommodation name,
restaurant name that belong to the cities Mumbai, Chennai,
Delhi, Calcutta, Bombay are displayed. Choices are available
in this approach

          a) Travel Agency Choice: The Fig 6 displays bottom
up traversal with travel agency choice. In this approach, the
travel agency queries to the end user for estimation. Based on
that estimation all the instances of the sub classes are                             Fig. 7 Bottom up with customer choice
restaurant, accommodation and travels are displayed. When
the end user specifies the instances this framework displays
actually which destination it belongs to, type and category of                         V PERFORMANCE EVALUATION
restaurant, accommodation and travels.
                                                                                Finally the performance of top down approach
                                                                      compared with bottom up approach for information retrieval
                                                                      speed .The following table shown the time taken to retrieve
                                                                      the results.




                                                                 81                                  http://sites.google.com/site/ijcsis/
                                                                                                     ISSN 1947-5500
                                                             (IJCSIS) International Journal of Computer Science and Information Security,
                                                             Vol. 8, No. 2, May 2010




TABLE I. PERFORMANCE COMPARISON OF TOPDOWN                         AND
BOTTOMUPAPPROACH FOR TRAVEL AGENCY CHOICE                                                      GRAPH II. COMPARISON GRAPH

Performance    Category   Top down                  Bottomup-
comparison                approach-                 Enduser
                          Enduser                   choice
                          choice


                          1342ms                    1319ms
               Luxury
 Time taken
    for
               Medium     1248ms                    1224ms
Information
 Retrieval

               Low        1170ms                     1143ms
                                                                              Graph II represents the performance comparison for end user
                                                                              choice using top down as well as bottom up approach. It
                                                                              shows that time taken to retrieve the information using bottom
                 GRAPH I. COMPARISON GRAPH                                    up approach is lesser than top down approach

                                                                                                 VI CONCLUSIONS
                                                                                       This paper proposes the usage of ontology for travels
                                                                              and tourism domain. It proposes a method to create and edit
                                                                              ontology dynamically and a method to query for information
                                                                              using ontology. This paper also proposes top down and bottom
                                                                              up approaches to extract information from ontology. A
                                                                              comparison of these two approaches is also provided in this
                                                                              paper. When budget of travel is known and no details of
                                                                              instances is provided bottom up approach can not be used. Top
                                                                              down approach is suitable. Thus the tradeoff between top
                                                                              down and bottom up approaches are not only based on the
                                                                              performance but also on their applicability.

Graph I represents the performance comparison for end user
choice using top down as well as bottom up approach. It                                            ACKNOWLEDGMENT
shows that time taken to retrieve the information using bottom                         Our thanks to Dr.R.Rudramoorthy,Principal,PSG
up approach is lesser than top down approach.                                 College of Technology and Mr.K.Chidambaram, Director,
                                                                              Grid and Cloud systems group, Yahoo software development,
       PERFORMANCE COMPARISON OF TOP DOWN AND
TABLE II.                                                                     India Private Limited for their support. This project is carried
BOTTOM UPAPPROACH FOR ENDUSER CHOICE                                          out in Grid and Cloud lab,PSG College of Technology.

    Top down -traveler choice         Bottom up- traveler choice                                         REFERENCES
                                                                               [1] Brooke Abrahamsand Wei Dai. Architecture for Automated Annotation
                                                                              and Ontology Based Querying of Semantic Web Resources
              3.29 ms                          3.19ms                          [2] Konstantinos Kotis, Semantic Web Search: Perspectives and Key
                                                                              Technologies.Karlovassi, 83200 Samos, Greece.




                                                                         82                                    http://sites.google.com/site/ijcsis/
                                                                                                               ISSN 1947-5500
                                                                (IJCSIS) International Journal of Computer Science and Information Security,
                                                                Vol. 8, No. 2, May 2010




[3]. Konstantinos Kotis, Dpaolo Ceravolo, Ernesto Damiani, Member, IEEE,
and Marco Viviani “Bottom-Up Extraction and Trust-Based Refinement of
Ontology Metadata” IEEE Transactions.
[4] Ling Li, Shengqun Tang, Lina Fang,Ruliang Xiao,Xinguo Deng,Youwei
Xu,Yang Xu, Visual Ontology Modeling Tool and Ontology Based Querying
of Semantic Web Resources, 31st Annual International Computer Software
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[5] P.H. Alesso, C. F. Smith. Developing Semantic Web Services. Canada:
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[6] P.H. Alesso, C..F. Smith, Developing Semantic Web Servces, A K Peters
ltd, Wellesey MA, Canada, Date,2004, pp.165-272.
[7] Siegfried Handschuh, Steffen Staab. Authoring and annotation of web
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[9] The Protégé project. http://protege.stanford.edu, 2002 On Knowledge and
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                          AUTHORS PROFILE

                 Dr G Sudha Sadasivam is working as a Professor in
                 Department of Computer Science and Engineering in PSG
                 College of Technology, India. Her areas of interest include
                 Distributed Systems, Distributed Object Technology, Grid
                 and Cloud Computing. She has published 5 books, 20
                 papers in referred journals and 32 papers in National and
                 International Conferences. She has coordinated two AICTE
                 – RPS projects in Distributed and Grid Computing areas.
                 She is also the coordinator for PSG-Yahoo Research on Grid
                 and Cloud computing.

                 Ms C Kavitha is working as a Senior Lecturer in Department
                 of Computer Science and Engineering in PSG College of
                 Technology, India. She is pursuing her research work in
                 Semantics in Large scale Distriduted systems. Her areas of
                 interest include Semantic Web Technology, Parallel
                 Processing and Data Structures. She has published 3 papers
                 in this area.



                 Ms M.Saravana Priya is a PG student doing her ME –
                 Software Engineering in CSE Department of PSG College of
                 Technology. Her area of interest        is Semantic Web
                 Technology. She has published 2 papers in this area




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                                                                                                           ISSN 1947-5500