From Requirements to Design: Model-driven Transformation or Mapping?

Abstract. In a case-based approach to software reuse, a requirements model may be used for indexing and retrieving other models and ideally all relevant software artifacts. In this context, the exact relationship between a requirements and a design model is of interest. We investigate this relationship in terms of model-driven approaches and discuss more precisely the question whether the transition from requirements to software design can be a model-based transformation or just a mapping. We show that it cannot be a model-driven transformation in the sense of such transformations from higher- to lower-level design models.

Experiences from Design and Implementation of Real-Life Database Backed Web Applications

Experiences from a novel design and implementation technique for database backed Web information systems are provided. The key idea is to use a state machine model to describe the user interface and the database functionality in a homogenous way. The implementation is then composed from several parts with potentially different techniques, for example either a pure HTML interface with all functionality at the server side or a Java applet with more functionality at the client side. With this virtual client/server model a prototype has been implemented successfully: A Europe--wide product marketing system for rural areas funded by the European Commission. KEYWORDS Database backed Web applications, information retrieval, information systems design and implementation, Web application design language. 1 Database Backed Web Applications This section introduces the research area of the system and gives an overview of the state of the art: Since the first days of the Web people have been se..

Dynamic Hyperlink Generation for Navigation in Relational Databases

This paper introduces a new design methodology for the integration of databases and the Web: The key idea of this approach is to use links to solicit user selections. Control elements are thus constructed of sets of links grouped together and called Passive HTML Controls (PHC). The links of a PHC are called elements. These links (elements) are a means of user interaction, no crossreferences or links for navigation. Each element has two parts: The anchor tag defining the link of the element and the content of the tag defining the output string of the element. This approach is reasonable for a typical Web application where most user interactions consist of browsing and collecting information from the database. The possible values for user input are predefined in these cases. Forms are only used where user input has to be gathered. Using groups of links instead of forms to interact with the database, the finite state machine model well known from static hypertext documents [5] can be remodelled to be suitable for dynamically generated hypertext [3]. It is proposed to view a static document as an abstract automaton that specifies the process of browsing within it. The linked structure of a document can usually be thought of as the state transition diagram of a FSM. Hence each document defines a state and the state transitions are provided by the hyperlinks. For dynamically generated documents, the FSM is remodelled: Definition 1 (Delayed Output State Machine) A Delayed Output State Machine is a quintupl

Using Communicative Acts in High-Level Specifications of User Interfaces for Their Automated Synthesis

User interfaces are very important for the success of many computerbased applications these days. However, their development takes time, requires experts for user-interface design as well as experienced programmers and is very expensive. This problem becomes even more severe through the ubiquitous use of a variety of devices such as PCs, mobile phones, PDAs etc., since each of these devices has its own specifics that require a special user interface

Transforming a Discourse Model to an Abstract User Interface Model ABSTRACT

User-interface design is still a time consuming and expensive task to do, but recent advances allow generating them from interaction design models. We present a model-driven approach for generating user interfaces out of interaction design models. Our interaction design models are discourse models, more precisely models of classes of dialogues. They are based on theories of human communication and should, therefore, be more understandable to humans than programs implementing user interfaces. Our discourse models also contain enough semantics to transform them automatically into user interfaces for multiple devices and modalities. This paper presents a two-step transformation approach with an intermediate abstract UI model. In this paper we concentrate user interface models by showing transformation rules. 1

A User Study with GUIs Tailored for Smartphones

Abstract. Web-based graphical user interfaces (GUIs) are mostly not tailored for small devices with touchscreens, such as smartphones. There is little scientific evidence on the conditions where additional taps for navigation are better or scrolling. Therefore, we conducted a user study in which we evaluated different ways of tailoring a GUI for a smartphone. Each participant performed the same task with two different layouts of the same GUI. We collected quantitative data through measuring task completion time and error rates, as well as qualitative data through subjective questionnaires. The main result is that minimizing the number of taps is important on a smartphone. Users performed significantly better when they could scroll (vertically), instead of tapping on widget elements (tabs). This preference was also reflected in their subjective opinions