Rolland C, Ben Achour C (1998) Guiding the construction of textual use case specifications. Data Knowledge Eng 25:125--160  Home/Search   Document Details and Download   Summary   Related Articles   Check

.... using a library of standard models and alternative sequences of use case events [4] 11] Rolland and Ben Achour present a process that begins with a context and initial scenario for a use case, and then guides the capture and completion of new scenarios and their integration into the use case [12]. The process employs guidelines for effective expression of use cases in prose, and rules that ask for more information or generate a new use case element from what is already known. The guidelines and rules are based on linguistic patterns and structures [12] The work on viewpoints discussed ....

....their integration into the use case [12] The process employs guidelines for effective expression of use cases in prose, and rules that ask for more information or generate a new use case element from what is already known. The guidelines and rules are based on linguistic patterns and structures [12]. The work on viewpoints discussed below provides process guidance for improving consistency among scenarios. Process guidance is an important benefit of the use of scenario networks. A scenario network aids in identifying missing scenarios and behaviors by forcing analysts to consider how the ....

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Colette Rolland and Camille Ben Achour, "Guiding the construction of textual use case specifications," Data and Knowledge Engineering Journal, vol. 25, no. 1--2, pp. 125--160, Mar. 1998, Also published as CREWS technical report 98-01.

....were then given 45 minutes to write the descriptions. After the experiment, there was a five minute feedback session. The experimental tasks are found at [10] The tasks are considered legitimate for this experiment since they replicate the tasks of the pilot study [9] and earlier CREWS studies [7, 13]. 3.4 Experimental Hypotheses It is not the intention of this work to discredit the CREWS Guidelines, since the CP Rules attempt to rationalise them. As such, various aspects of the CREWS Guidelines have been streamlined to form part of the CP Rules. However, our overall proposition was that the ....

ROLLAND, C., BEN ACHOUR, C.: `Guiding the construction of textual use case specifications', Data and Knowledge Eng. J., 1998, 25 (1-2) pp. 125-160

....have too few [16] or too many steps, or too much exceptions, i.e. too many alternative courses . What actors do not participate in any use case [16] 6 Related work Some of the results of the ESPRIT project CREWS, especially style and content guidelines for textual specification of use cases [20] have influenced our work. Their approach, implemented in the CREWS SAVRE and L Ecritoire tools, combines natural language processing (NLP) techniques and linguistic patterns, guiding the construction of use cases and providing a, much more powerful than ours, ambiguity detection mechanisms. We ....

C. Rolland and C. Ben Achour. Guiding the Construction of Textual Use Case Specifications. Data & Knowledge Engineering Journal, 25(1--2), 1998.

....engineering task. Recent studies concerning the use of scenarios in industrial projects [11] have clearly proved this fact and pointed out the necessity of more detailed definitions on scenario construction to increase their use in real situations. This is in complete agreement with Rolland et al. [12] and Sutcliffe [13] who think that there is little understanding about the usage and production of scenarios. The variety of interpretations, syntax and construction mechanisms for scenarios goes as far as showing up basic contradictions. For instance, with respect to the scenario construction ....

....while for us scenarios capture situations of the application domain. Besides, 20] proposes the utilisation of formalisms as an alternative to natural language. Our approach consists of using natural language with rules for eliciting and then modelling scenarios. We agree with Rolland [12] that the use of natural language in scenarios implies an easy to understand model though it may be attached with ambiguities and inconsistencies. These drawbacks can be reduced by employing a well defined UofD vocabulary such as our LEL [29] complemented with a verification process such as ....

Rolland C, Ben Achour C. Guiding the construction of textual use case specifications. Data Knowl Eng 1998;25:125--160

....by (manual) translation into the specification language LOTOS [2] A number of other researchers have attached pre and postconditions (or initial and final states) to scenarios. Rolland and Ben Achour use initial states of agents and final states of episodes to guide the writing of use cases [6]. Rolland et al. attach initial and final states (analogous to pre and postconditions) to scenarios in their L Ecritoire tool in support of a heuristic to guide the search for additional goals [7] Maiden et al. attack the problem of missing scenarios with a method supported by their CREWS SAVRE ....

C. Rolland and C. Ben Achour. Guiding the construction of textual use case specifications. Data and Knowledge Engineering Journal, 25(1--2): pages 125--160, Mar. 1998.

....four different scenario based approaches have been developed with the aim of supporting system requirements acquisition and validation in a systematic way. Two approaches deal with the requirements acquisition from real world scenes [Haumer 98] and from natural language scenario descriptions [Rolland 97] Rolland 98a] Two other approaches deal with the requirements validation through systematic scenario generation coupled to scenario walkthrough [Sutcliffe 98] and scenario animation [Dubois 98] The project hypothesis is that each of the approaches might be useful in specific project ....

C. Rolland, C. Ben Achour, Guiding the construction of textual use case specifications. Data & Knowledge Engineering Journal Vol. 25 N 1, pp. 125-160, (ed. P. Chen, R.P. van de Riet) North Holland, Elsevier Science Publishers. March 1997.

....L Ecritoire after the famous student cafe at Sorbonne university) supports not only the structured text presentation of scenarios but also their content analysis. This process leads to a formal knowledge base of CREWS 11 models, but also to the discovery of new goals in the text of the scenario [Rolland and Ben Achour 1997]. 3. Systematic generation of validation scenarios: Another critical issue is the question of coverage: how many scenarios are enough to characterise the requirements to a system This question can only be answered with respect to reference domain knowledge. However, typical reference models ....

Rolland, C., Ben Achour, C. 1997. Guiding the construction of textual use case specifications. Data & Knowledge Engineering, to appear.

....will enable stakeholders later on to recognize modeling errors, impacts of changing assumptions, etc. For the special case of textual scenario descriptions, additional support is provided through structuring authoring guidelines and partially automated natural language understanding and indexing [57]. animate capture initial model initial model new model new model existing system existing system new system new system change specification reverse analysis legacy integration change implementation future scenario future scenario current scenario current scenario change envisioning ....

Rolland, C., Ben Achour, C. 1997. Guiding the construction of textual use case specifications. Data & Knowledge Engineering 25, 1/2, 125-160.

....about the application domain, reports about problematic issues with the existing system and opportunities for a new one, and so on. The scenarios provided are assumed to be found in such preliminary material; we do not cover the process of eliciting and elaborating such scenarios see, e.g. [68, 34, 61, 64] for guidelines and research efforts in that direction. Scenarios are expressed here as event trace diagrams [68] a notation chosen for its popularity and its simplicity. The generated specifications are expressed in the KAOS goal based language [11, 42] so that a number of formal reasoning ....

....specifications, namely, the elaboration of narrative temporal sequences of interactions, the translation of such narratives into the diagrammatic notation used as input language to our inference procedure. Guidelines and research efforts to tackle those two problems can be found in, e.g. [68, 34, 61, 64]. 3.2 Representing scenarios A scenario was defined in Section 1 as a temporal sequence of interaction events among different agents in the restricted context of achieving some implicit purpose(s) To represent such scenarios we use the popular event trace diagram notation [68] Figure 2 shows a ....

C. Rolland and C. Ben Achour, "Guiding the Construction of Textual Use Case Specifications", Data & Knowledge Engineering Journal Vol. 25 No. 1-2, March 1998, 125-160.

....instance scenario. Finally, mixed scenarios [Rolland 98a] are those that have some parts at the instance level and others at the type level. Finally, scenarios can be expressed using different notations ranging from the informal, semi formal to the formal. Informal scenarios use natural language [Rolland 98b] Erickson95] Holbrook 90] videos [Wood 94] Haumer 98] story descriptions, and are valuable in those cases where the user community is unwilling (or unable) to deal with formal notation. Semi formal scenarios use a structured notation like tables [Potts 94] and scenario scripts [Rubin 92] ....

.... through multimedia scenarios fulfils its expected goals [Haumer 98] to infer goals specifications from operational scenarios [VanLamsweerde 95] and, in the CREWS L Ecritoire approach, to discover new goals through scenario analysis [Rolland 98a] The CREWS L Ecritoire approach [Rolland 98a] Rolland 98b] uses a bi directional goal scenario coupling allowing movement from goals to scenarios and vice versa. The global solution is in two parts : when a goal is discovered, a scenario can be authored for it and once a scenario has been authored, it is analysed to yield goals. By exploiting the ....

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C. Rolland, C. Ben Achour, Guiding the Construction of Textual Use Case Specifications. Data & Knowledge Engineering, Vol.25, N1, pp.125-150, 1998.

....and therefore ensure that the future system will meet the requirements of its users. In the CREWS 1 project, four different scenario based approaches have been developed with the aim of supporting requirements acquisition from real world scenes [4] and from natural language scenario descriptions [5], 6] and requirements validation though scenario walkthrough [7] and scenario animation [8] The hypothesis of the project is that each of the approaches might be useful in specific project situations which are not well tackled by existing analysis methods and therefore, that it is worth looking ....

C. Rolland, C. Ben Achour, Guiding the construction of textual use case specifications. Data & Knowledge Engineering Journal Vol. 25 N 1, pp. 125-160, (ed. P. Chen, R.P. van de Riet) North Holland, Elsevier Science Publishers. March 1997.

....goal. This was apparent when we applied the goal driven approach as embodied in the EKD method to several domains air traffic control, electricity supply, human resource management, tool set development [ELEKTRA97] Loucopoulos94] This led to some formalisation of the goal formulation [Prat97] Rolland97a] Yet, domain experts need to discover the goals of real systems. It is thus evident that help has to be provided so that goal modelling can be meaningfully performed. This help must (a) facilitate the work of the domain expert by getting over the problem of the fuzzy nature of goals (b) help ....

.... goals [Haumer98] to infer goals specifications from operational scenarios [van Lamsweerde98] and to discover new goals through scenario analysis [Rolland98a] As an example of an approach which combines goal modelling and scenario authoring let us consider the CREWS L Ecritoire approach [Rolland97a] Rolland98a] developed within the CREWS ESPRIT project. CREWS L Ecritoire uses a bi directional coupling allowing movement from goals to scenarios and vice versa. The complete solution is in two parts : when a goal is discovered, a scenario can be authored for it and once a scenario has been ....

C. Rolland, C. Ben Achour, Guiding the construction of textual use case specifications. Data & Knowledge Engineering Journal Vol. 25 N 1, pp. 125-160, (ed. P. Chen, R.P. van de Riet) North Holland, Elsevier Science Publishers. March 1997.

....discover goals identifying collections of system functions that are necessary to define a completely functioning system. Guiding rules supporting the refinement strategy help discovering goals at a lower level of abstraction than a given one. So far, the CREWS L Ecritoire approach was detailed in [4] [5] 1] 2] its process was modelled [7] 6] it was implemented in a software prototype [8] and the scenario authoring guidelines were evaluated [3] However, there is still little evidence concerning the effectiveness of each individual CREWS L Ecritoire guiding rule for goal analysis and ....

C. Rolland, C. Ben Achour. Guiding the Construction of Textual Use Case Specifications. Data & Knowledge Engineering Journal Vol. 25 N 1, Elsevier Science. Mar. 1997.

....process [12] seems to confirm this trend. However, as show our enquiries at several major European companies, requirement engineers still need help in the process of authoring scenarios [10] 3] In this paper, we are interested in the guidance of the so called scenario authoring process [20]. By scenario authoring, we mean to write, clarify, complete and conceptualise scenarios. In addition, we focus on textual scenarios, that is to say descriptions of stories of system usage in (more or less structured) natural language. In the literature, textual scenarios are also referred to as ....

....is one possible behaviour limited to a set of purposeful interactions taking place among several agents [4] On the contrary, use cases describe several possible uses of a system. Therefore, a use case is composed of several scenarios. We say how to integrate scenarios into a use case in [20]. The Figure 1 presents the model of scenarios with the OMT notation [23] reference is composed of Normal Scenario Exceptional Scenario Scenario Flow of Actions Atomic action Agent Resource Object Concurrency Sequence Iteration Constraint Flow Condition 1 1 is based is based is described by ....

[Article contains additional citation context not shown here]

. C. Rolland, C. Ben Achour, Guiding the Construction of Textual Use Case Specifications. Data & Knowledge Engineering Journal, Vol 25, N°1-2, pp 125-160, March 1998.

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C. Rolland, C. Ben Achour, Guiding the construction of textual use case specifications, to appear in Data and Knowledge Engineering Journal, 1998.

....provided in the form of enactable guiding rules embodied in a computer software environment called L Ecritoire. As a result, it is possible to guide the requirements elicitation process through interleaved goal modelling and scenario authoring. Whereas rules for scenario authoring can be found in [3, 28], we propose here a basis for guidance in goal modelling. There are three kinds of rules, each for determining one of the three kinds of relationships mentioned above namely, AND, OR, and Refinement. Each rule generates a menu of goals for the Requirement Chunk Author (RCA) to evaluate and select. ....

....the semi structured textual form to represent the scenarios associated to requirement chunks. As shown in Fig. 5, each action of a scenario is expressed in a separate line as a natural language clause preceded by a reference number. The formal semantics of natural language clauses is detailed in [3, 28]. 2.2 The hierarchy of requirement chunks The three types of relationships among requirement chunks lead to a hierarchical organisation of RCs, as illustrated in Fig. 5. RC1.1 AND AND G1.1:Withdraw cash from ATM in a normal way Sc1.1 G1.1 1 :Withdraw cash from ATM by treating the exception ....

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C. Rolland, C. Ben Achour, Guiding the construction of textual use case specifications. Data & Knowledge Engineering Journal Vol. 25 N° 1, pp. 125-160, (ed. P. Chen, R.P. van de Riet) North Holland, Elsevier Science Publishers. March 1997.

....to organise collections of scenarios of different kinds : textual, graphical, animated, functional or not, etc. 14] The AND OR Refine relationships are semantic relationships which relate scenarios according to the nature of their contents. The solution proposed has been applied on examples [13, 15], and on real case studies [10] 1 This work is partly funded by the Basic Research Action CREWS (ESPRIT N 21.903) CREWS stands for Cooperative Requirements Engineering With Scenarios. The paper is organised as follows. The next section is an overview of the CREWS approach for scenarios based ....

C. Rolland, C. Ben Achour, Guiding the construction of textual use case specifications. To appear in Data and Knowledge Engineering Journal, 1998.

....to infer goals specifications from operational scenarios [28] and to discover new goals through scenario analysis [23] The purpose of this paper is to assess the strengths and weaknesses of an approach to requirements engineering that uses goal scenario coupling. The CREWS L Ecritoire approach [22, 23] developed within the CREWS ESPRIT project uses a bi directional coupling allowing movement from goals to scenarios and vice versa. The complete solution is in two parts : when a goal is discovered, a scenario can be authored for it and once a scenario has been authored, it is analysed to yield ....

C. Rolland, C. Ben Achour, Guiding the construction of textual use case specifications. Data & Knowledge Engineering Journal Vol. 25 N° 1, pp. 125-160, (ed. P. Chen, R.P. van de Riet) North Holland, Elsevier Science Publishers. March 1997.

....paper ends with a discussion of the implications on CREWS tools for UC authoring and analysis. 2 2. Use Case authoring 2. 1 CREWS use case model CREWS has undertaken an extensive literature review (e.g. 9] 5] 10] 11] to develop a model of UC, together with a guidance process for authoring UCs [12]. The model is in two parts. The first describes contextual information which links the UC to other UCs, relevant goals, glossaries of terms, and decisions underpinning the design of the UC. The second describes the set of scenarios which constitute the UC. These are divided into a main normal ....

....The actions of a path of actions are strictly sequenced and can be constrained by conditions. Scenario actions can be interactions between two agents, or actions of internal type. CREWS provides guidelines for writing and refining scenarios, and for integrating different scenarios into a UC [12]. Guidelines exist to structure scenarios, make scenarios more complete, precise, and consistent in terminological use [13] CREWS also provides software assistance to apply the guidelines [8] It analyses narrative text to catch the semantics of the text and map the text contents into instances ....

C. Rolland, C. Ben Achour. Guiding the Construction of Textual Use Case Specifications. In Data & Knowledge Engineering Journal, Vol 25, N°1-2, (ed. P. Chen, R.P. van de Riet), North Holland, Elsevier Science Publishers, pp. 125-160, March 1998

....them. The last section discusses the results presented in this paper. 2. The conceptual definition of scenarios A scenario expresses an example of behaviour of a system. Thus, a scenario is one possible behaviour limited to a set of purposeful interactions taking place among several agents [7]. The CREWS approach defends a tight coupling of goals and scenarios into requirement chunks [7, 8] To any scenario is attached a goal. Goals express in part the requirements for the designed system. They are written as a verb together with one or several parameters, and they are illustrated by ....

....of scenarios A scenario expresses an example of behaviour of a system. Thus, a scenario is one possible behaviour limited to a set of purposeful interactions taking place among several agents [7] The CREWS approach defends a tight coupling of goals and scenarios into requirement chunks [7, 8]. To any scenario is attached a goal. Goals express in part the requirements for the designed system. They are written as a verb together with one or several parameters, and they are illustrated by scenarios. In the following, we call a scenario by the name of the goal it illustrates. The figure ....

[Article contains additional citation context not shown here]

. C. Rolland, C. Ben Achour, Guiding the Construction of Textual Use Case Specifications. Data and Knowledge Engineering Journal, Vol 25 N° 1,1998.

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Rolland C, Ben Achour C (1998) Guiding the construction of textual use case specifications. Data Knowledge Eng 25:125--160

No context found.

C. Rolland and C. Ben Achour. Guiding the construction of textual use case specifications. Data and Knowledge Engineering Journal, 25(1--2): pages 125--160, Mar. 1998.

No context found.

C. Rolland, C. Ben Achour, Guiding the Construction of Textual Use Case Specifications, Data & Knowledge Engineering Journal, Vol. 25 No 1-2, 1998, North Holland Elsevier Science Publ., pp. 125--160.

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