A Conceptual, User-Centric Approach to Modeling Web Information Systems


Arno Scharl, MIS Department, Vienna University of Economics, Augasse 2-6, A-1090 Vienna, Austria (currently employed as visiting research fellow at the Electronic Commerce Network, Curtin University of Technology, Perth, Western Australia). scharl@wu-wien.ac.at


Abstract

Due to a constantly changing environment, a poor understanding of the user’s needs and preferences, as well as a lack of willingness to modify existing organizational structures and decision models, the full economic potential of Web Information Systems (WIS) has not been realized by now. The data object types of the presented meta model, the Extended World Wide Web Design Technique (eW3DT), provide hypertext designers with a conceptual, user-centric framework and graphical notation for the construction of both, reference and customized models, during the software development process of commercial WIS. A reference model as a normative concept represents an abstraction of a typical company, its functional units, or its (Web) Information Systems and is intended to streamline the design and implementation of complex applications at reduced costs. As precondition for pursuing a partial globalization strategy, eW3DT distinguishes between technical and content-specific responsibilities for designing, implementing, and maintaining WIS.


Introduction

Reference models are characterized by a high level of abstraction and provide designers of customized, company-specific models with a referential solution which merely has to be adapted according to individual corporate strategies and technical restrictions. In the case of WIS, they have to integrate a conceptual data and navigational model and - by choosing a system-specific optimal level of abstraction - should equally be applicable for structured as well as unstructured information. As one of the primary means of standardized communication regarding WIS architectures these models support cooperative efforts to design such systems. In order to serve as an efficient interface to people with very heterogeneous knowledge and expectations, diagrams have to include the essential information in an illustrative, clearly arranged, and comprehensible way.

Figure 1. WIS Analysis & Design

Results of research activities formulated in recipient-oriented reference models may be used by any organization to build up new WIS from scratch or to extend and adapt existing ones. The reference model together with the deduced conclusions represent a basic guideline for deducting customized models, streamlining the implementation of complex WIS at reduced costs (see Figure 1).

By avoiding structural inconsistencies and mistakes companies are able to improve the quality of their systems, usually at low costs in comparison with acquiring the necessary know-how from external commercial organizations. However, empirical validation of hypotheses concerning success factors of WIS in different lines of business remains vital since standard software metrics frequently fail to evaluate the structure of WIS adequately. Furthermore, no valid theory currently exists to "assess formally whether a conceptual model of a hypertext is clear to readers. The only feasible alternative is testing the hypertext in as real a situation as possible" [20].

Extended World Wide Web Design Technique (eW3DT)

In this section methods and tools for WIS analysis and design are described and compared. Due to the limitations found in many existing design concepts, Bichler and Nusser developed the World Wide Web Design Technique (W3DT) together with a working prototype called WebDesigner [HREF1] which supports the graphical, interactive design of complex WIS from a user’s perspective [5]. Comparable academic or commercial modeling tools like the WebArchitect [HREF2], SchemaText [HREF3], or Microsoft's FrontPage [HREF4] to name just a few provide similar "authoring-in-the-large" [7] functionalities. However, most available products do not address responsibilities for content production, system implementation, or regular maintenance.

Other approaches like the widely accepted RMM methodology [15] or OOHDM [23;24] are especially suited for highly structured information domains [2]. In most cases they succeed traditional hypermedia design techniques like HDM [8;9] which themselves are under constant development. In contrast to these database-oriented concepts, W3DT was built from scratch to support the requirements of unstructured, hierarchical WIS and to visualize them from a recipient’s perspective. Utilizing practical experiences in developing WIS, the graphical notation of the design tool was further refined and used to analyze a number of deployed applications. With special regard to reference modeling of commercial WIS, the Extended World Wide Web Design Technique (eW3DT) was developed [22].

The concept of hierarchy is essential for the architecture of any real-world WIS [25]. On the other hand - as far as database-centric hypermedia applications are concerned - there is no adequate substitute for entity-relationship or object-oriented approaches. In this sense both W3DT and eW3DT are not intended to replace existing hypertext design methodologies but to act as hierarchically oriented, complementary communication tools between researchers, system analysts, and the management responsible for the decision to implement WIS. For developing increasingly complex applications, therefore, it is recommended and necessary to integrate the user-centric eW3DT with technical, more database-centric meta models like RMDM, HDM, OOHDM, or any of the other approaches based on entity relations. This integration has to be carefully planned in accordance with existing corporate design and implementation guidelines and would ideally be supported by an integrated WIS analysis and design tool supporting each of the three model layers of Figure 1.

Developing Applications with eW3DT

The Dexter Hypertext Reference Model divides the structure of hypertext systems into three different layers: the run-time layer for accessing individual documents, the content-specific within-component layer, and the storage layer [11]. In the case of WIS, every reference model has to integrate a conceptual data and navigational model [14]. It should satisfy the need for modeling structured as well as unstructured information by choosing a system-specific optimal level of abstraction. Accordingly, the data object types of the presented, document-oriented meta model eW3DT focus on the storage layer of the Dexter model, describing the structure of hypertext systems as a finite set of hierarchically arranged and associatively linked elements.

The composition of the document itself, described by the within-component layer, is functionally dependent, outside of the hypertext model per se and therefore not part of the reference model. Since the simple run-time layer of the Dexter model, which relies on the fundamental concept of the instantiation of a component, is already predetermined from the perspective of the content provider, eW3DT merely has to provide an appropriate set of data and navigational components.

Besides its content, every hypertext document includes a logical and a layout structure [16]. The WIS architecture specifies a number of processes which are responsible for presenting documents in conformity with the specifications of other layers. The relative importance of all these components varies depending on the specific data object type and its instantiation.

By combining inductive and deductive methods the process of creating conceptual WIS representations is both top-down and bottom-up. As depicted in Figure 1, eW3DT provides a framework for the construction of both abstract reference and customized, company-specific models during the software development process of commercial WIS (Figure 2). Note the difference regarding the level of abstraction between meta models (eW3DT, RMDM, HDM etc.), reference models, and customized models [22;13]. Analogous to similar approaches in business engineering, developing WIS requires a sequence of revolutionary and evolutionary processes (Figure 2; [21]). Analysis, design, and prototyping exclusively rely on internal network architectures ("Revolution"). After thoroughly testing system consistency, every designer has to make sure that the contents as well as their presentation meet all quantitative and qualitative requirements. As soon as unrestricted access is granted to the general public, there follows a cyclic sequence of usage, analysis, (re-)design, and implementation ("Evolution").

Figure 2. Software development process of commercial WIS

Hypertext documents are authored, redesigned, or eliminated by the WIS designer or the department(s) responsible for the content of a particular domain. The process of WIS creation requires creativity and intelligent planning during the initial analysis, design, and implementation which is referred to as "internal (r)evolution" in Figure 2. For that reason Martin [19] introduces the term "intelligent evolution". With special emphasis on corporate business behavior, he compares three types of evolution with the classic Darwinian evolution based on the survival of the fittest:

a. Internal (r)evolution during the pre-deployment phase:

 

 

b. External Evolution:

One of the problems regarding modeling and developing hypermedia applications is the strong interdependency between presentation (user interface) and representation (explicit structuring) of published information. Many meta models and design methods for traditional client-server architectures lack the necessary object types for modeling this interdependency and are better suited for highly structured segments. This was one of the reasons behind the development of W3DT respectively eW3DT. By conveying the intrinsic structure in a clear manner eW3DT also provides analysts with an increased understanding of the actual application. Therefore, in addition to designing WIS, it may also be used to visualize the structure of deployed systems and to compare them with each other. A simple example of how to generate eW3DT diagrams from existing documents will be presented below.

Object Type Definition

Not every marginal structural analogy increases economic or technical utility. In order to serve as an efficient interface to people with very heterogeneous knowledge and expectations, diagrams have to include the essential information in a consistent, non-redundant, and readable way [3]. They serve as interpretative guideline for these people and usually incorporate design recommendations to improve the usability [1] of WIS as well. Diagrams which rely on eW3DT are a user-centric combination of structural and process diagrams [17] requiring an explicit explanation of symbols. This explanation will be given in the following sections.

Every eW3DT data object type represents a content-specific variation of a standard symbolic element, depicted in Figure 3, and is equivalent to an atomistic unit of the Dexter Hypertext Reference Model.

Figure 3. Standard Symbolic Elements

In this paper the data object types will be referred to as information object types, the objects themselves as information objects or documents. Independent of iconic similarity and real equivalence to a given object (hypertext compound document), every information object type defines a general profile for describing the characteristic attributes of this object. Each of these profiles corresponds to a set of abstractions commonly found in WIS. The attributes assign information on structural position, maintenance intensity, and organizational integration to the modeling constructs. In addition to the name of each object, the eW3DT standard symbolic element includes the following specifications:

In case of the standard symbolic element for WIS analysis (see Figure 3), the rectangular symbols representing different types of hypertext compound documents incorporate a completely different set of attributes in comparison with the eW3DT design meta-model. While the color respectively the shading of objects represents their accumulated number of HTTP requests during a certain period (N_Hits), the style of connecting links between the documents represents the frequency with which these links where followed by customers. In addition to that, the average viewing time of WIS documents in seconds is displayed in the field (Avg_Vtime). With the (Info) button, detailed information about the object in question is accessible (e.g., a list of host names / IP addresses of the most important visitors, aggregated number of entries and exits, and so forth). Being part of the user interface, the two arrow symbols in the bottom right corner do not represent an attribute of the object but provide the analyst with the option to move between lower-level and upper-level diagrams.

Figure 4 categorizes the object types of eW3DT into the three functional segments: "Information", "Navigation", and "Structure". For each information object type with the exception of DBase there is a static class and a class for dynamically generated documents. In the case of DBase, internal and external data structures are distinguished since the content structure itself is inherently dynamic - a fact which doesn't require explicit visualization. Structural variability is the relevant characteristic to make the distinction between static and dynamic information objects. If the structure is changing, the dynamic process becomes part of the architecture, independent of technical realization. Even if documents are automatically generated out of database queries, their inherent character might be of static nature. With the help of the elements of Figure 4 it is possible to construct intuitively comprehensible and illustrative graphical descriptions of complex WIS from a user’s perspective, no matter if they are intended for a real organization (customized model) or for an industry-specific analysis (reference model).

Figure 4. Object Types of eW3DT, Categorized into the Functional Segments Information, Navigation, and Structure

Classification of Information Object Types

Content Design

A Page object is used to model multimedia compound documents. In many cases these objects represent the logical end of a hierarchical tree. As already mentioned, the internal structure of a Page itself is not supported by the eW3DT meta model.

Alternative navigational paths and access mechanisms belong to the object type Menu. The respective objects are usually found at higher hierarchical levels of WIS. They are strongly influenced by considerations regarding the optimal width and depth of the contents offered - a tradeoff between usability criteria and efforts to reduce the maximum number of hierarchical levels. In contrast to menus, an Index contains a complete enumeration of links, for example a company’s staff or a list of available products. Especially for statically implemented Index documents, maintenance is vital due to the well known fact that links pointing to missing, inactive, or irrelevant sources reduce the perceived quality of WIS substantially.

Interaction includes various interactive elements, characterized mainly by their content and layout structures. For the designer of a conceptual model, technical details are only of secondary importance. During the earlier stages of the WIS development process it does not matter whether an interaction will finally be implemented using FORM-fields of HTML, Java-Applets, MS ActiveX-objects, or comparable technologies.

The electronic distribution of software as well as any application-specific transmission of data blocks requires secure and efficient mechanisms to transport files of various formats and sizes in a platform-independent way from the content provider to WIS users. These mechanisms may be visualized with the eW3DT object type File. In this context the term "presentation” as used above also refers to the execution of an application on the respective target platform.

Figure 5. eW3DT object type DBase

Due to an ever increasing demand for up-to-date and consistent information it seems justified to expect many company-wide internal databases to be connected to more and more complex WIS over a relatively short period of time. Economically it is not feasible and definitely not in compliance with the basic assumptions behind a reference model to deal with all these databases explicitly. Any attempt to do so would result in a redundant remodeling of existing internal structures, not to mention the heterogeneous character of corporate database architectures. With eW3DT, only user inputs which lead to the creation of new database entries or the update of stored information are taken into consideration. The reserved symbol for these user inputs is the eW3DT object type DBase (see Figure 5), available in two different representations: internal and external.

While internal DBase-objects refer to various corporate databases, the external ones include cooperative databases or databases held by other institutions. For objects marked with a lock appropriate security mechanisms have to be implemented due to the sensitivity of the provided information. Again, since technical details are only of secondary relevance for conceptual modeling, eW3DT does not distinguish between different protocols like SSL, S-HTTP, SET, etc. or between the hierarchical network or application layer these protocols rely on. The [R]ead- and [W]rite-flags indicate the user's right to access individual entries while the star symbols on the bottom right corner of the object describe the update intervals required, similar to the maintenance intensity of documents. '*' is used for static permanent data, '**' for occasionally updated entries (e.g., user profiles, marketing information, compiled Web statistics), and '***' for highly volatile transactions records (e.g., payment data, shopping lists, log-files documenting access patterns and user behavior, etc.).

Hierarchical Structuring

With regard to the increasing complexity of contents and navigational elements, the complete structure of a WIS cannot be shown in just one single diagram. Since it causes an unnecessary loss of information, the object type Diagram of W3DT - predecessor of eW3DT - was eliminated. The required reduction in complexity is now achieved by hierarchical diagram structuring with the Primary Structuring Element as shown in Figure 4. The information object type as well as additional attributes of the corresponding document located in the lower-level diagram are already part of the upper-level diagram, thus increasing clarity and usefulness of the graphical representation.

External Links are used to depict hyperlinks to external information sources which are not part of the corporate WIS, for example those of other companies, standardization comities, or governmental organizations. The object type Multiple Sources plays a vital part in reducing redundancy within the diagrams and may be found where multidimensional selections offer access to large amounts of data (the product lines depicted in Figure 8 provide a good practical example for this object type). Multiple destinations, on the other hand, frequently emerge from the implementation of an Index and are represented by the dynamic version of the navigational object type Representative Link which will be described in the following section.

Navigation Design

The navigation within hypertext structures as well as the development of WIS are non-linear, non-sequential activities which require an appropriate visual (symbolic) representation. Navigational design has to counteract the reduction of coherence in WIS which frequently arises due to an inadequate consideration of the specific linguistic features of hypertext environments. Static Links are implemented permanently, only structural redesigns of WIS require an adaptation. Dynamic Links refer to customized, automatically generated documents. The Representative Link (REP) as a sub-type of the Dynamic Link points to different versions of static information which are delivered depending on the existence of certain conditions or responding to a certain user behavior specified in advance. As already mentioned, multiple destinations within WIS are modeled with Representative Links as well. Last, but not least, the Horizontal Link (INCLUDE) - not a hyperlink in the narrow sense - enables designers to deal with heterogeneous information objects (so-called composites, using the terminology of the Dexter Hypertext Reference Model; [11]). In order to increase flexibility and reduce the number of necessary object types at the same time, a dedicated symbol for bi-directional links does not exist in eW3DT. Bi-directional access structures, paths, or guided tours may always be constructed using combinations of uni-directional navigational object types.

Applications of eW3DT

In order to demonstrate the semantic relationships between the eW3DT data object types described above, the process of analyzing deployed WIS will be demonstrated in the following. The real-world WIS document of Figure 6 is compared with its abstract eW3DT representation depicted in Figure 7. In addition to that, the simple retailing reference solution visualizes standard WIS components of an electronic retailing storefront at reduced complexity.

Figure 6. Compaq Product Showroom [HREF5]

WIS Analysis

While reference models are useful mainly for the purpose of deducting customized and technical models, eW3DT diagrams of deployed WIS help to understand, analyze, and improve these applications. For this purpose the actual diagram should represent the structure of the system as close to reality as possible. However, as in most cases internal technical details are either not relevant or not available at all (e.g., if an analyst concentrates on a competitor’s WIS), using eW3DT for analyzing existing documents or sites focuses on the same level of abstraction as the customized design models discussed in the introduction of this paper.

Figure 6 shows the sub-component "product showroom” of Compaq’s corporate WIS (an application which is in no way related to eW3DT). However, in the course of constructing a reference model for the computer industry, many deployed WIS were analyzed and compared, and the document above basically was chosen for its typical contents, a clear layout, and the rather low complexity as far as the number of menu items and cross references are concerned.

If we take a closer look at the structure of the document, it is possible to distinguish between different types of information objects. It is obvious that the {Product Showroom} itself is a Menu for accessing different product categories offered for the home computing segment. Three Indices represent collections of {Desktops}, {Notebooks}, {Monitors}, and {Printers}. {Handelds}, however, are modeled as a Page since the document provides information on just one single product ("C Series 2015c"). While {Compaq Classics} is a typical example of a Menu specifying a hierarchical access pattern, the two Interactions support direct access to current news and to new products for informed customers who exactly know in advance what they are looking for.

Figure 7. eW3DT-diagram {Compaq Product Showroom}

Reference Model for the Retailing Industry

In order to demonstrate the applicability of eW3DT for more complex user interactions on a conceptual level this section presents a very abstract example of how a reference model for commercial retailing transactions in the computer industry might be structured and visualized. Designing WIS seen as an incremental and opportunistic human activity includes "backtracking and erratic switching among the following activities: thinking about ideas, production, reorganization, modification, and evaluation” [20]. During all these sub-processes and for the {Company Storefront} as the first hierarchical layer in particular, every designer should bear in mind recommendations with regard to a limited number of unrelated elements appearing in a single document. Being able to build and represent complex structures does not imply that the recipient absorbs them in the intended way. As a consequence, every hypermedia access structure has to find a balance between horizontal and vertical integration density.

After accessing the {Company Storefront} - e.g., http://www.companyname.com/index.html - the WIS user is provided with a {Company Profile} as well as a number of {Product Families} to identify his general requirements. As already mentioned above, this access mechanism is a good example for the object type Multiple Sources. Having selected a certain category, the potential customer is able to choose between {Product Variations} more specifically. Information on the product in question is accessible via a Representative Link pointing to the description {Product X} with optional {Technical Details} for further information. Note that in contrast to W3DT-models [4], sub-diagrams relying on the syntax of eW3DT may have more than one single entry point. Should the {Bargaining Process} turn out to be satisfactory for both parties, the customer is able to immediately place an online-order by filling out the {Order form}. Since being associated via a Horizontal Link, this Interaction is already included in the document {Product X}. If all specifications have been entered correctly, a separate market transaction is triggered between the seller of the PC and a financial clearing institution. The secondary, value adding process has to settle the accounts between seller and buyer, no matter if the financial clearing institution is a bank, a credit card organization, an issuer of electronic money, or any combination of these virtual payment methods. As soon as a certain form of payment is agreed upon and verified by the seller, the database entries {Accounting}, {Hardware Turnover}, and {Customer Profiles} are updated and a {Confirmation of Order} including the estimated time of delivery can be sent immediately, either per e-mail or directly via a dynamic Page. In contrast to the {Shopping List} the three DBase-objects {Accounting}, {Hardware Turnover}, and {Customer Profiles} contain sensitive information which is visualized by the lock on the left side of the symbols. The access privileges of the customer, indicated by the [R]ead- and [W]rite-flags, only allow him to view and edit the {Shopping List} as well as certain segments of the {Customer Profile}.

The whole transaction is completed with the physical distribution of the product. In case of immaterial goods (e.g., informational products like software, news, financial information services, etc.) the actual delivery of the product is executed without delay, a customized File sent to the buyer eliminates the need for physical distribution.

Figure 8. eW3DT-diagram {Company Storefront}

Conclusion

With the continuing introduction of new technologies, strategic management decisions have to consider innovation as a crucial parameter, particularly as far as information and communication technologies are concerned. Innovation substantially reduces the practical value of traditional communication models. This paper purported to examine the role of conceptual, user-centric modeling of WIS as a primary means of standardized communication between academic research, management, and the designers of WIS. The development and potential of eW3DT as the "language" used to consistently communicate industry-specific knowledge has been presented together with two examples for WIS analysis (inductive) and design (deductive). The results suggest that there still is a lack of non-redundant, readable meta models for WIS which do not ignore the hierarchical, recipient-oriented structure of current WIS. Complementary to approaches primarily focusing on technical issues, eW3DT is intended to drive structural design and to streamline the decision processes necessary for implementing complex WIS.

However, the eW3DT meta model merely represents a starting point. Additional research on the integration with database-centric approaches is needed. The syntax of eW3DT should be made available for existing WIS modeling prototypes like the already mentioned WebDesigner in order to be of practical utility. Finally, the applicability of the proposed framework for customized transactions of higher complexity and adaptive systems has to be evaluated. This assessment will possibly lead to a further extended meta model, providing additional information object types as well as an optimized graphical representation.

References

  1. Bachiochi, D. et al. Usability studies and designing navigational aids for the World Wide Web. Proceedings for the 6th International World Wide Web Conference. M.R. Genesereth and A. Patterson (ed.). Santa Clara: 511-517.
  2. Balasubramanian, V., Ma, B.M. and Yoo, Y. A systematic approach to designing a WWW application, Communications of the ACM, 38, 8 (August 1995), 47-48.
  3. Becker, J., Rosemann, M. and Schuette, R. Grundsaetze ordnungsmaessiger Modellierung”, Wirtschaftsinformatik, 37, 5 (October 1995), 435-445.
  4. Bichler, M. and Nusser, S. SHDT - the structured way of developing WWW-sites. Proceedings of the 4th European Conference on Information Systems (ECIS '96). J.D. Coelho et al (ed.). Lisbon: 1093-1101.
  5. Bichler, M. and Nusser, S. Modular design of complex Web-applications with W3DT”. Proceedings of the 5th Workshops on Enabling Technologies: Infrastructure for Collaborative Enterprises (WET ICE '96). Stanford: IEEE Computer Society Press, 328-333.
  6. Chatzoglou, P.D. Use of methodologies: an empirical analysis of their impact on the economics of the development process. European Journal of Information Systems, 6, 4 (December 1997), 256-270.
  7. Freisler, S. and Kesseler, M. Document Engineering. http://www.schema.de/SCHEMAPublikationen/Vortrag/doenghtm.htm (September 1997).
  8. Garzotto, F., Mainetti, L. and Paolini, P. Hypermedia design, analysis, and evaluation issues, Communications of the ACM, 38, 8 (August 1995), 74-86.
  9. Garzotto, F., Paolini, P. and Schwabe, D. HDM - a model-based approach to hypertext application design, ACM Transactions on Information Systems, 11, 1 (January 1993), 1-26.
  10. Hansen, H.R. Conceptual framework and guidelines for the implementation of mass information systems, Information & Management, 28, 2 (February 1995), 125-142.
  11. Halasz, F. and Schwartz, M. The Dexter Hypertext Reference Model, Communications of the ACM, 37, 2 (February 1994), 30-39.
  12. Hansen, H.R. and Schweeger, T. Austrian home survey: IT infrastructure and market potential of interactive services. Proceedings of the 4th European Conference on Information Systems (ECIS '96), J.D. Coelho et al. (ed.). Lisbon: 201-211.
  13. Hars, A. Referenzdatenmodelle - Grundlagen effizienter Datenmodellierung. A.-W. Scheer (ed.). Wiesbaden: Gabler, 1994.
  14. Hofmann, M. Hypertextsysteme - Begrifflichkeit, Modelle, Problemstellungen, Wirtschaftsinformatik, 33, 3 (June 1991), 177-184.
  15. Isakowitz, T., Stohr, E.A. and Balasubramanian, P. RMM: A methodology for structured hypermedia design, Communications of the ACM, 38, 8 (August 1995), 34-44.
  16. Khalfallah, H. and Karmouch, A. An architecture and a data model for integrated multimedia documents and presentational applications, ACM Multimedia Systems, 3, 5/6 (November 1995), 238-250.
  17. Lohse, G.L. et al. A classification of visual representation, Communications of the ACM, 37, 12 (December 1994), 36-49.
  18. Marent, C. Branchenspezifische Referenzmodelle fuer betriebswirtschaftliche IV-Anwendungsbereiche, Wirtschaftsinformatik, 37, 3 (July 1995), 303-313.
  19. Martin, J. Cybercorp: The New Business Revolution. New York: Amacom, 1996.
  20. Nanard, J. and Nanard, M. Hypertext design environments and the hypertext design process, Communications of the ACM, 38, 8 (August 1995), 49-56.
  21. Oesterle, H. Business Engineering: Prozess- und Systementwicklung, Band 1: Entwurfstechniken. Berlin, Heidelberg: Springer, 1995.
  22. Scharl, A. Referenzmodellierung kommerzieller Masseninformationssysteme. Idealtypische Gestaltung von Informationsangeboten im World Wide Web am Beispiel der Branche Informationstechnik. Frankfurt, Vienna: Peter Lang, 1997.
  23. Schwabe, D. and Rossi, G. The object-oriented hypermedia design model, Communications of the ACM, 38, 8 (August 1995), 45-46.
  24. Schwabe, D., Rossi, G., and Barbosa, S. Systematic hypermedia application design with OOHDM. Proceedings for the 7th ACM Conference on Hypertext (Hypertext '96). http://www.cs.unc.edu/~ barman/HT96/P52/section1.html#intro (May 1997).
  25. Takahashi, K. and Liang, E. Analysis and design of Web-based information systems. Proceedings of the 6th International World Wide Web Conference (WWW6). M.R. Genesereth and A. Patterson (ed.). Santa Clara: 377-389.

Hypertext References

HREF1
http://wwwi.wu-wien.ac.at/w3dt/
HREF2
http://www.nttlabs.com/~kt/WebArchitect/
HREF3
http://www.schema.de/site/site-d/kapitel/schemat0.htm
HREF 4
http://www.microsoft.com/frontpage/
HREF 5
http://www.compaq.com/athome/showroom/


Copyright

Arno Scharl, © 1999. The author assigns to Southern Cross University and other educational and non-profit institutions a non-exclusive licence to use this document for personal use and in courses of instruction provided that the article is used in full and this copyright statement is reproduced. The author also grants a non-exclusive licence to Southern Cross University to publish this document in full on the World Wide Web and on CD-ROM and in printed form with the conference papers and for the document to be published on mirrors on the World Wide Web.


Proceedings ]


AusWeb99, Fifth Australian World Wide Web Conference, Southern Cross University, PO Box 157, Lismore NSW 2480, Australia Email: "AusWeb99@scu.edu.au"