Session 2.2:  Requirements in Practice

Derived Requirements Generation The DRAS methodology
David Bar-On (Israel) and Shmuel Tyszberowicz (Israel)
In the early stages of system development, many requirements interdependencies exist. Interacting requirements may conflict with one another and they may impact (change or enhance) other requirements as well. Those interdependencies should be identified as early as possible in the development lifecycle. Conflicts should be resolved, so as to avoid the cost and schedule overhead that comes when detecting them late in the development process. Properly identifying the interactions, during the requirements elicitation and analysis, results in new and modified Derived Requirements (DRs). These DRs resolve interactions and undesirable conflicts. An important kind of requirements which interact with other requirements is Crosscutting Functional Requirements (FRs). These requirements change or override the function of other requirements they crosscut, usually for certain states of product functionality. The DRAS (Derived Requirements generation based on Actions and States) methodology presented in this paper helps both to identify FRs that crosscut other FRs and to generate the derived or modified requirements. To identify crosscutting requirements, the methodology matches actions used by requirement and the system modes and states related to the requirements. When the same action is used by two requirements it might indicates that one of the requirements may crosscut the other. In addition to actions directly used, DRAS takes into account actions implicit by them. For a specific action Act (referred to by a requirement), DRAS uses the following implied-actions: (a) Actions that are activated as a consequence or result of using Act, or (b) Actions that Act is the consequence of their use.

Context Aware Communication Services in “Active Museums”
Sadek Jbara (Israel),Tsvi Kuflik (Israel),Pnina Soffer (Israel)  and Oliviero Stock (Italy)
Nowadays, technology enables museums to become “active”. Shortly, museum visitors will be equipped with smart personal devices and the museum environment can track and interact proactively with visitors by offering them various services. Visitors often tend to visit museums in groups, mainly with family or friends, yet most of today's mobile museum guides focus on supporting the individual visitor. The technologies for museum visitor guides and other mobile guides described in various papers allow supporting interaction between individuals or groups of visitors, since it is known that such interaction especially in museums enhances the visit experience. These services can be abstracted to a small subset of context-aware communication services. The service agent developed in the framework of the PIL project is a prototype system for a general communication services framework.