International Journal of Interactive Mobile Technologies (iJIM) - Volume 5, Issue 4, October 2011 PAPER MOBILE TOURIST GUIDE – AN INTELLIGENT WIRELESS SYSTEM TO IMPROVE TOURISM, USING SEMANTIC WEB Mobile Tourist Guide – An Intelligent Wireless System to Improve Tourism, using Semantic Web http://dx.doi.org/ijim.v5i4.1695 Hosam F. El-Sofany1, and Samir A. El-Seoud2 1 Cairo Higher Institute for Engineering, Computer Science, and Management, Cairo, Egypt 2 Technische Universität Darmstadt (TU Darmstadt), Darmstadt, Germany Abstract—With the recent advances in Internet and mobile technologies, there are increasing demands for electronic access to tourist information systems for service coordina- tion and process integration. Mobile computing and mobile devices are used to implement various tourist services (e.g. electronic tourist guides, digital interactive maps, and tour- ist e-commerce transactions). However, due to disparate tourist information and service resources such as airlines, hotels, tour operators, it is still difficult for tourists to use them effectively during their trips or even in the planning stage. Neither can current tourist portals assist tourists pro- actively. To overcome this problem, we propose the analysis, design, and implementation of the “Mobile tourist guide" system, that access through wireless devices and use Seman- tic Web technologies for effective organization of informa- tion resources and service processes. The proposed system provides the users with various services such as: 1) display- ing the shortest path between the sources and destinations the visitors specify, 2) displaying general information of shops, newest events of the plaza and shops, 3) provides service of hotel, restaurant and cinema-ticket reservations, 4) provides user-friendly administration service. The Admin can manage the position, blocking path details, general in- formation of hotel, restaurant, shops and plaza, and reser- vation details via web browser without changing the frame- work of the system. The system prototype has been devel- oped on the top of Java 2 Micro Edition which offers an ideal platform for the development of full-fledged, interac- tive and portable applications tailored for resource con- strained mobile devices. The paper presents our develop- ment experiences and highlights its main advantages and limitations in relation to the implementation of such kind of applications. Index Terms—Electronic tourist guide, Mobile tourist guide, Semantic Web technology, Tourist Information System, Tourist application. I. INTRODUCTION Tourism is a leading industry in the e-business. There are several reasons behind this fact. Tourism is an infor- mation-intensive industry with a long value chain. Since 1960s this industry represents a classical field of informa- tion and communication technology applications. Charac- teristics of electronic tourism marketplace lead to many challenges. One of them is growing need for interoperabil- ity between information systems, allowing seamless in- formation exchange between tourism organizations. The traditional solution for interoperability issues was to de- velop interfaces between each pair of communication sys- tems, but development and maintenance of such programs are too expensive and not flexible enough for the elec- tronic tourism marketplace. There have been many at- tempts to standardize data exchange within tourism elec- tronic markets in order to reach global interoperability. As a result there are some global standards used only by large companies and some standards developed for the needs of small companies, but used only on national level [1]. The World Tourism Organization predicts that by 2020, tourist arrivals around the world will increase over 200%. Tourism has become a highly competitive business all over the world. Competitive advantage is increasingly driven by the advancement of information technology and innovation. Currently, the Internet is the primary source of tourist destination information for travelers. With the recent advances in hardware and software technologies, the Internet is quickly evolving towards wireless adoption. New mobile applications running on these devices provide users with easy access to remote services available anytime and anywhere, and will soon take advantage of the ubiquity of wireless networking in order to create new virtual worlds. Besides, intelligent software agents can run on these devices and can provide personalized assistance to tourists during their trip. To- gether with traditional information agents such as hotel broker agents, tour planning agents, and other disparate tourist resources, they form a Multi-Agent Information System, for collaborative and intelligent assistance to tourists. At the same time, Semantic Web technologies have been maturing to make e-commerce interactions more flexible and automated. Ontology defines the terms used to present a domain of knowledge that is shared by people, databases, and applications. In particular, ontology en- codes knowledge, possibly spanning different domains as well as describes the relationships among them. Currently, ontology is actively being developed in various business domains. The Semantic Web provides explicit meaning to the information available on the Web for automated proc- essing and information integration based on the underly- ing ontology. Our aim in this project is to describe charac- teristics of the electronic tourism as well as challenges related to the tourism electronic marketplace and to dis- cuss how semantic web technologies can help to resolve these challenges. In this research, we intend to expand tourist coordina- tion and integration towards complete support by employ- ing all the above-mentioned technologies. The main chal- lenge of our system is to provide an effective coordination and integration of disparate information and service re- 4 http://www.i-jim.org http://dx.doi.org/ijac.v4i4.1695 PAPER MOBILE TOURIST GUIDE – AN INTELLIGENT WIRELESS SYSTEM TO IMPROVE TOURISM, USING SEMANTIC WEB sources anytime, anywhere, as well as the provision of personalized assistance and automation to the tourists, each having different preferences and support require- ments that often being changed during the trip. With the help of ontology, our system can help tourists better un- derstand and guide them to specify their needs and prefer- ences collaboratively, so that the appropriate information and services resources could be located from the Semantic Web. Because scalability and flexibility, tourists cannot be flexibly assisted in a centralized manner. The assistance of increasingly powerful mobile devices becomes the ena- bling technologies. Under individual’s instructions and preferences, intelligent software agents within the system can be delegated to help recommend, plan, and negotiate personalized activities and schedules, thereby augmenting the user’s decisions collaboratively. We introduce a scal- able, flexible, intelligent, and multi-agent “Mobile tourist guide" system, with agent clusters for tourist service coor- dination and integration. Each agent cluster comprises several types of agents to achieve the goals of the major tasks of a tourist’s trip, such as, information gathering, preference matchmaking, planning, service brokering, commuting, and mobile servicing. The agents also make use of ontology from the Semantic Web to search infor- mation and make recommendations to the tourists. Fur- ther, we detail how this can be effectively implemented with Web service and Semantic Web technologies, inte- grating disparate Internet tourist resources The research goal is to analysis, design, and implement the “tourist guide" system, that access through wireless devices (such as mobile telephones, Personal Digital As- sistants - PDAs, and laptops). The following are some services and functionality provides by the proposed re- search study:  The system provides general information of hotel, res- taurant, shops, hospitals, and companies. As well as the newest events of the plaza and shops.  The system provides service of hotel, restaurant and cinema-ticket reservations.  The system provides service of displaying the shortest path between the sources and destinations the visitors specify.  The system provides user-friendly administration ser- vice. The Admin can manage the position, blocking path details, general information of shops and plaza, and reservation details via web browser without changing the framework of the system.  The system tackles the difficulties of displaying the routes on different floors and many problems in mobile web development. II. SYSTEM OVERVIEW The Semantic Web as the next generation web is the vi- sion of having background knowledge about the meaning of web sources stored in a machine-processable and – interpretable way. The area of tourism is highly dynamic area that currently already extensively uses the available Internet technologies. However, the shortcomings of the existing technology are that information finding and ex- traction as well as the interpretation of the information contained in the web sources is left to the human user. The management and interoperation of semantically diverse tourism information systems are facilitated by Semantic Web technology that provides methods and standards, which allow accurate access to information as well as flexibility to comply with needs of tourism information system users and administrators. In this research project we introduce a new Semantic Web framework that can enable knowledge sharing and reuse. The Semantic Web uses agent technologies to formally model information represented in web resources. This makes it accessible to humans and computers working together, perhaps in con- junction with intelligent network services such as search agents. The "Mobil tourist guide" system represents a relatively new trend in the field of tourism and involves the use of Semantic Web technology and mobile devices as elec- tronic tourist guides. While much of the underlying tech- nology is already available, there are still open challenges with respect to design, usability, portability, functionality, and implementation aspects. This research study presents the analysis, design and implementation of the "Mobil tourist guide" system, that allows the users to download these personalized applications either directly to their mo- bile device or first to a PC and then to a mobile terminal (through infrared or Bluetooth). Thereafter, network cov- erage is not further required as the applications execute in standalone mode and may be updated when the user re- turns online. The system prototype will use Java 2ME, which offers an ideal platform for the development of full- fledged, interactive and portable applications tailored for resource constrained mobile devices. In our research study we consider number of important issues related to the Semantic Web that belongs to four categories: Semantic Web languages, ontologies, semantic markup of Web pages, and Semantic Web services [2]. Semantic Web Languages: In order to represent infor- mation on the Semantic Web and simultaneously make that information both syntactically and semantically inter- operable across applications, it is necessary to use specific languages. There are a lot of such languages around, and most of them are based on XML, XML Schemas, RDF, and RDF Schemas, all four developed under the auspices of W3C and using XML syntax. Ontologies: Ontology comprises a set of knowledge terms, including the vocabulary, the semantic interconnec- tions, and some simple rules of inference and logic for some particular topic. Ontologies applied to the Web are creating the Semantic Web. Ontologies provide the neces- sary armature around which knowledge bases should be built, and set grounds for developing reusable Web- contents, Web-services, and application. Ontologies facili- tate knowledge sharing and reuse, i.e. a common under- standing of various contents that reaches across people and applications. Semantic Markup: Ontologies merely serve to standard- ize and provide interpretations for Web content, but are not enough to build the Semantic Web. To make Web content machine-understandable, Web pages and docu- ments themselves must contain semantic markup, i.e. an- notations which use the terminology that one or more on- tologies define and contain pointers to the network of on- tologies. Semantic Web Services: Intelligent, high-level services like information brokers, search agents, information fil- ters, intelligent information integration, and knowledge iJIM ‒ Volume 5, Issue 4, October 2011 5 PAPER MOBILE TOURIST GUIDE – AN INTELLIGENT WIRELESS SYSTEM TO IMPROVE TOURISM, USING SEMANTIC WEB management, are what the users want from the Semantic Web. They are possible only if a number of ontologies populate the Web, enabling semantic interoperation be- tween the agents and the applications on the Semantic Web, i.e. semantic mappings between terms within the data, which requires content analysis. A. Semantic Web and Tourism Information Systems The Semantic Web appears as a promising technology for implementing E-tourism information system. The Se- mantic Web constitutes an environment in which human and machine agents will communicate on a semantic basis [8]. One of its primary characteristics, viz. shared under- standing, is based on ontologies as its key backbone. On- tologies enable the organization of tourism objects around small pieces of semantically annotated tourism objects [9]. Items can be easily organized into customized tourism services and delivered on demand to the user, according to her/his profile and business needs. The term "Semantic Web" encompasses efforts to build a new WWW architecture that enhances content with for- mal semantics. That means, content is made suitable for machine consumption, as opposed to content that is only intended for human consumption. This will enable auto- mated agents to reason about Web content, and produce an intelligent response to unforeseen situations. “Expressing meaning” is the main task of the Semantic Web. In order to achieve that objective several layers of representational structures are needed. They are presented in the Figure 1, among which the following layers are the basic ones [8]: - The XML layer, which represents the structure of data, - The RDF layer, which represents the meaning of data, - The Ontology layer, which represents the formal common agreement about meaning of data, - The Logic layer, which enables intelligent reasoning with meaningful data. The important property of the Semantic Web architec- ture (i.e., common-shared-meaning and machine- processable metadata), enabled by a set of suitable agents, establishes a powerful approach to satisfy the E-tourism requirements. The process is based on semantic querying and navigation through tourist services, enabled by the ontological background. The Semantic Web can be ex- ploited as a very suitable platform for implementing an E- tourism information system, because it provides all means for electronic tourism: ontology development, ontology- based annotation of tourism objects, their composition in tourism recourses and active delivery of the tourism ser- vices through E-tourism portals. The main style related to our research in the Semantic Web is the layered architecture. The layered architecture consists of a number of layers organized hierarchically as in Figure 1. Each layer provides a service to its upper layer and serves as a client to the layer below. This kind of architecture depends on the sequence of incremental steps, which means the increasing level of abstraction; if the function of one layer changes, this means that two other layers may be effected. In the tourism industry, the Semantic Web technologies offer considerable benefits in terms of travel management, Figure 1. Layers of the Semantic Web content and document management, knowledge manage- ment, supply chain management and integration of dis- tributed applications and services [16,17]. The Semantic Web technologies help in the realization of the vision of the intelligent wireless Web in the following ways: Deeper understanding of the semantics of document con- tent and travel task structure using ontologies, will help the mobile tourist in intelligent information retrieval, ex- traction and processing, thereby helping him to accom- plish elements of a travel plan. Through the introduction of ontological reasoning, Semantic Web techniques are suitable for flexibly discovering abilities in using informa- tion that was not specifically designed or intended for a particular use case. Given the dynamic nature of travel processes, this would help in on-the fly resource discovery and integration. Mobile tourists will be able to dynami- cally locate highly specific data and services on an as- needed basis [18]. Travel enterprises very often undertake their processes in different ways. Differences in the meanings of terms make collaboration difficult. The use of shared ontologies and semantic standards will ensure increased interopera- bility across devices, platforms and applications [19]. Separation of presentation and data, as ensured by the Semantic Web technologies, will ensure the use of the same middleware tier for both mobile and fixed network clients. The Semantic Web technologies can provide a standardized way to interpreting context, enabling both human and software agents to infer new context knowl- edge and consequently take intelligent actions. B. System Architecture Our basic Semantic Web framework illustrated in Fig- ure 2, provides the tourist with different types of tourism services. In this research study we focus on the implemen- tation of these services that provide the tourist with the following services: - General information of hotel, restaurant, shops, hospi- tals, and companies - The newest events of the plaza and shops. - Hotel, restaurant and cinema-ticket reservations. - displaying the shortest path between the sources and destinations the visitors specify, and - Semantic search. On the other hand, the system allows the administrators to manage the position, blocking path details, to purplish the general information of shops and plaza, and reserva- tion details via web browser. 6 http://www.i-jim.org PAPER MOBILE TOURIST GUIDE – AN INTELLIGENT WIRELESS SYSTEM TO IMPROVE TOURISM, USING SEMANTIC WEB Figure 2. Basic Semantic Web Model for Tourist Guide System C. Using Mobile technology for E-Tourism M-tourism means the provision of tourism services on wireless devices: portable computers, PDA’s, mobile tele- phones and Tablet PC. Our mobile tourist guide system has functions to enter and to organize the tourism objects in the database and to make them available for tourists and administrators using the E-tourism management informa- tion systems (TMIS) portals in which the tourism process and its activities have been structured. The M-tourism object management systems are now compatible for all kind of user devices, the conventional desktop PC as well as the mobile devices laptop, PDA and mobile telephone. - The advantages: The advantages of mobile tourism refer mostly to the mobile user: a great flexibility, an improved tourist schedule is possible, increased pro- ductivity during dead moments and just in time tour- ism. - Difficulties and limitations: Nevertheless they have very small screens, limited memory capacity and the large diversity of mobile devices obstruct a good tour- ism experience. In the M-tourism field we notice that the tourism services must answer to specific condi- tions. We will have to get around the technical restric- tions so we can create a good tourism services. The usage of video, audio, clear interfaces and divided tourism services must contribute to this. Furthermore we will have to adapt the content to the needs of the mobile user. Because the user has a fragmentized time schedule, we will have to be sure that the tour- ism objects are not to long. Dividing the knowledge in smaller modules offers a solution. III. ANALYSIS AND DESIGN METHODS We build first the general architecture of the system, set the graphical user interface and design the structure of the database that stores the required data and information. In order to achieve our goals we defined the following tasks: A. System Analysis The analysis phase is the main phase in which the as- sessment system requirements are identified in more de- tails. The goal of this phase in the system development is to represent the system goals into defined functions and operations of the intended applications. The tourist guide system requirements are documented in a complementary set of artifacts (flowcharts, use case diagrams, system se- quence diagrams…). Each artifact provides a different perspective of the system under design and contains dis- tinct requirements. The combination of these perspectives establishes the tasks that are to be accomplished by the system.  Information Gathering Techniques: By assisting of some specialist employees from different tourism companies, all the system services and materials are checked. The following are some information gather- ing techniques that used in the tourist guide system analysis. - Interviews: The most common technique for gathering requirements is to sit down with the clients (tourists, tourism companies, and admin- istrators) and ask them what they need. Our dis- cussion would help us plan out ahead of time, based on the type of requirements that we are looking for. - Prototyping: We use this technique for gathering requirements. In this approach, we gather pre- liminary data and requirements that we use to build the initial version of the system. - UML (Universal Modeling Language) use-cases is used also in the analysis of the tourist guide system as a model tool, in which the functional requirements are extracted and described along with a scenario of the flow of events. The system requirements are classified in two types: functional and non-functional requirements.  Functional requirements: The tourist guide system allows different types of users to interact with the sys- tem according to given privileges. There are three main users of the system: administrator, tourism company, and tourist, as shown in Figure 3. The sys- tem provides the following applications (services) to each user: Figure 3. The main users of the system iJIM ‒ Volume 5, Issue 4, October 2011 7 PAPER MOBILE TOURIST GUIDE – AN INTELLIGENT WIRELESS SYSTEM TO IMPROVE TOURISM, USING SEMANTIC WEB 1. The administrator application: This application pro- vides the tourism administrator with simple tools to manage the information of the tourist guide system. The following are some features provided by the ad- ministrator application: - Activate/inactivate the system. - Import and export the system' database - Send automatic email immediately containing the new password whenever the user changes his/her password. - Administer the basic data and information of the system: hotels, restaurant, shops, hospitals, com- panies, and etc. 2. The tourism company application: This application provides the tourism companies with various tools to construct the system services. The following are some features provided by the tourism company applica- tion: - Change account password - Manage (add, update, delete and display) all the tourist guide system services. 3. The tourist application: This application provides the tourist with interactive tools (web-based and mobile- based) to use the system services. The following are some features provided by the tourist application: - Create (and change) account password - Search for information of hotel, restaurant, shops, hospitals, and companies. - Search for the newest events of the plaza and shops. - Hotel, restaurant and cinema-ticket reservations. - displaying the shortest path between the sources and destinations the visitors specify. - Access the tourist guide system through wireless devices (such as, Mobile phone, PDA and Tablet PC) and take quick tour.  Non-functional requirements: In this part, we have verified and proved the system' aspects and interfaces that are not directly related to the functional behavior, such as: usability, reliability, supportability, perform- ance, and security: - Usability: Is the system providing a coherent and flexible user interface that can be used easily with all users? Has the system an obvious component which allows the user to navigate easily? Are the system applications easy to use by tourism compa- nies and tourists? Is the system adaptive to user needs? Is the tracking component working prop- erly and produce the expected results - Supportability: Can the system be easily modified or extended easily? Can tourism companies and administrators add materials easily? - Contents and Design: Are the design and contents of the system satisfactory to tourists, tourism com- panies, and system administrators? What are their feedbacks? Does the system cover well the topics? Are they useful and meet their goals? Quality of texts, images, sounds, and clips? We will compare the progress of tourists. - Performance: Are the performance requirement concerned with quantifiable attributes of the sys- tem, such as response time, throughput availability and accuracy? - Flexibility: Is the system flexible, since it will be used regularly with a new set of initial data and can accommodate changes in database such as modifying the contents? - Security: Is the system preventing unauthorized users to access the system?  Hardware and software resource: We have used some software during our first prototype of the sys- tem development such as: Windows XP professional, Windows Server O/S, Microsoft office Excel, Micro- soft Word, SQL Server database system, MS Visual Studio.Net, and Photo Shop. To extend our research work, by using Semantic Web and Mobile technologies, we used other new languages and tools including: XML- eXtensible Markup Language, XML Schemas, RDF- Resource Definition Framework, RDF Schemas, OWL- Web Ontology Language, and Java 2ME. B. System Design Any successful web-based system should have an easy to use graphical user interface (GUI) that facilitates its use and flexibility. Thus the proposed system should possess an attractive GUI that is suitable to the potential users. The interface should be tested by its users and updated whenever necessary. The tourist guide system interface is entirely web- based, and doesn’t necessitate any technical skills from the potential users. The system is appropriate for web- based search, with access to the Internet, or mobile-based search using the wireless devices.  Database design: Database is an important compo- nent in our system. We have used Microsoft SQL Server database as a database management system (DBMS). The DBMS stores the following entities: - Tourist (name, id, nationality, tel, email, …) - accompany (name, id, relation, …) - Hotel (name, tel, add, …) - Hospital (name, tel, add, …) - Shops (name, tel, email, add, …) - Restaurants (name, tel, email, add, …) - Companies (name, tel, email, add, …) - Conferences (name, type, location, start_date, end-date, …) - Services (Sno, type,…) - Travel_agent (id, name, tel, fax, email, add, …) - Tours (location, arrive_time, pickup_time, loca- tion, …) - Admin (id, name, tel, email, …). We have chosen the entity-relationship model to repre- sent the database design. As shown in Figure 4, we pre- sent the initial entity-relationship diagram of the tourist guide system, that contains the main entities (tables) used for creating the system database. 8 http://www.i-jim.org PAPER MOBILE TOURIST GUIDE – AN INTELLIGENT WIRELESS SYSTEM TO IMPROVE TOURISM, USING SEMANTIC WEB Figure 4. Basic entity relationship diagram  Tourists, especially first time tourists, will feel com- fortable. This is because all what they need to know about national sights; restaurants and other interesting places will be in front of them by pressing a few but- tons. A. Advantages of the System The proposed research study is of considerable signifi- cance due to the following facts:  The new generation of the Web, the so-called Seman- tic Web, appears as a promising technology for im- plementing E-tourism systems.  Tourists will be able to save time by knowing the information they need without having to call or spend time on the internet searching.  E-tourism and M-tourism (Electronic and Mobile tourism) research areas can benefit from Semantic Web technologies. The Semantic Web technology has enabled by a set of suitable agents, which seems to be powerful enough to satisfy the E-tourism re- quirements fast, and just-in-time.  First time drivers, or drivers who came from abroad will be able to find their way quickly and smoothly.  The hotels, hospitals, companies and other important sectors will not receive unnecessary calls like calls that ask about the building’s site or departments’ phone numbers, etc. This is because this kind of in- formation will be available on the proposed system.  The Semantic Web has opened new horizons for internet applications in general and for E-tourism in particular.  The system guides the researchers and guests that came for conferences to spend an easy tour in the country.  It is extremely important for Tourism Authority to improve the tourism services, thus promoting signifi- cant changes among tourism institutions.  The system guides the visitors that came from outside for festivals and Eid period, for places where celebra- tion is, without wasting their time.  The study is significant to the researcher who will be working on open, hot and recent research areas of the next generation Web. IV. CONCLUSION AND FUTURE WORK In this paper, we have presented the architectural details and design for “Mobile tourist guide" system, that used Semantic Web technologies for effective organization of information resources and service processes. The pro- posed system allows the users to: display general informa- tion of hotels, restaurant, shops, hospitals, companies, etc; display the shortest path between the sources and destina- tions the visitors specify; the newest events of the plaza and shops; provide service of hotel, restaurant and cin- ema-ticket reservations; and allow the administrators to  The study is significant to researchers who will be working on building Web-based system using new techniques (such as; Semantic Web, and Mobile tech- nology) and new languages and tools (such as; XML- eXtensible Markup Language, XML Schemas, RDF- Resource Definition Framework, RDF Schemas, OWL- Web Ontology Language, and Java 2ME ).  The study allows the (new) employees and workers to use his/her wireless devices (PDA, Mobile telephone, and Smart phones) anytime and anywhere to know the places that they are looking for easily and quickly. iJIM ‒ Volume 5, Issue 4, October 2011 9 PAPER MOBILE TOURIST GUIDE – AN INTELLIGENT WIRELESS SYSTEM TO IMPROVE TOURISM, USING SEMANTIC WEB manage the position, blocking path details, general infor- mation of hotel, restaurant, shops and plaza, and reserva- tion details via web browser without changing the frame- work of the system. The system prototype has been developed on the top of Java 2 Micro Edition which offers an ideal platform for the development of full-fledged, interactive and portable applications tailored for resource constrained mobile devices. The paper presented our vi- sion of the Semantic Web and its potential benefits to tourism information systems. In tourism much data is only loosely structured or given in texts – a mode that is too weak for rich querying. The Semantic Web provides additional mechanisms adequate for dealing with these structures, enabling new applications for commerce and communications, especially. We have proposed a Seman- tic web framework that supports multiple platforms (in particular wireless mobile ones) and a methodology for the analysis and design of Mobile tourist guide system. As for future research, our key focus is about thr im- plementation of “Mobile tourist guide” ontologies. De- spite the considerable efforts toward the construction our system ontologies for agent interoperation, some difficul- ties and challenges are still open. Throughout the paper, we assume ontologies to be consistent and available to the agents. In reality, many ontologies are redundant in the sense that they present the same domain with little or no interoperation between different ontologies. The ontolo- gies play a main role in the system implementation, as they provide a shared representation of the domain and of the concept that the agents need to use. REFERENCES [1] Egypt Authority Web site: http://sharepoint.emot.gov.eg [2] Fayed Ghaleb, Sameh Daoud, Ahmad Hasna, Jihad Jaam, Samir A. El-Seoud, and Hosam El-Sofany, "E-Learning Model Based On Semantic Web Technology". International Journal of Computing & Information Sciences (IJCIS), Vol. 4, No. 2, P63-71, August 2006. 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HARMONISE: Towards Interop- erability in the Tourism Domain. Proceedings of Information and Communication Technologies in Tourism 2003, ENTER 2003, pp. 58-66, Helsinki: Springer, 2003. AUTHORS Hosam F. El-Sofany is with Cairo Higher Institute for Engineering, Computer Science, and Management, Cairo, Egypt Samir A. El-Seoud is with Technische Universität Darmstadt (TU Darmstadt), Darmstadt, Germany. This article is an extended version of a paper presented at the Interna- tional Conference on Computer Aided Learning (ICL2010), held at Has- selt University, Hasselt, Belgium, in September 2010. Received June 10th, 2011. 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