Mike Robey

A Case Study: GQM and TSP in a Software Engineering Capstone Project

This paper presents a case study, describing the use of a hybrid version of the team software process (TSP) in a capstone software engineering project. A mandatory subset of TSP scripts and reporting mechanisms were required, primarily for estimating the size and duration of tasks and for tracking project status against the project plan. These were supplemented by metrics and additional processes developed by students. Metrics were identified using the goal-question-metric (GQM) process and used to evaluate the effectiveness of project management roles assigned to each member of the project team. TSP processes and specific TSP forms are identified as evidence of learning outcome attainment. The approach allowed for student creativity and flexibility and limited the perceived overhead associated with use of the complete TSP. Students felt that the experience enabled them to further develop and demonstrate teamwork and leadership skills. However, limited success was seen with respect to defect tracking, risk management, and process improvement. The case study demonstrates that the approach can be used to assess learning outcome attainment and highlights for students the significance of software engineering project management

Petri Net Script: a visual language for describing action, behaviour and plot

Current techniques for behavioural specification provide the ability to describe individual methods of action, interaction and behaviour, but do not allow scripting of a complex behavioural sequence as is required for a virtual actor within the plot of a stage-play. These existing specification techniques are also designed primarily for use by computing experts, usually as a text based language, and are therefore not easily accessible by laymen. The paper presents Petri Net Script (PNS), a new graphical language for specification of virtual actor behaviour. PNS provides a graphical interface to behavioural scripting that enables specification of actions and interactions for virtual actors that can then interact with human actors in real time. A quantitative justification as to the effectiveness of the new language is evaluated through comparison of required complexity to achieve a simple behaviour against that of a more traditional specification technique using an adaptation of T.J. McCabes (1976) Cyclomatic Complexity.

Integrating design formalisms in software engineering education

Reflecting current industry trends, most computer science and software engineering degree programs place strong emphasis on the Unified Modelling Language (UML) as a graphical approach to software design and requirement analysis. To a lesser extent, formal methods utilizing languages like Z are found within many degree programs, but often only as a recommended elective as suggested by IEEE Computing Curricula 2001. Data flow diagrams (DFDs) and other graphical techniques are also included in the curricula of many programs. The various approaches are often taught in isolation, with little connection demonstrated between them. We describe the benefits of an integrated approach when teaching these design formalisms to undergraduate students. A significant educational benefit of an integrated approach is that it fosters a deeper understanding of the notational semantics available in any one technique. Co-development utilizing multiple techniques empowers the student to exploit the strengths of alternate representations of the same model. It also provides a rigorous means to analyse the correctness and consistency of graphical design representations by utilizing more formal methods.

Generating Web applications from use case scenarios

The major emphasis in developing design tools for Web applications has been that of content. User requirements are often assumed. We would argue that the requirements are as significant for Web applications as they are for any other application. Use case modelling is regarded as an ideal tool for capturing software requirements. We describe a requirements driven approach for generating the source code required for a Web based application. Use case modelling is an ideal mechanism for determining Web site navigability because it encapsulates all of the desired sets of user interactions with the Web application. Using this it is possible to map user interactions to sets of request/response events and from there to a sequence of event trees for each use case. These event trees can then be used to automatically generate the code for the required Web based application. The process which we call WEBGen, is used to determine a mapping between each use case scenario step and a set of request/response events. The number of possible request/response events is relatively small which makes the mapping between scenario steps and code a manageable task. WEBGen is demonstrated by using it to develop the code for an online practical registration system.

Using dependence graphs to assist manual and automated object oriented software inspections

Many researchers have demonstrated the value of software inspections in finding and fixing defects early in the development process. However, manual inspection can be a labour-intensive process. We present a tool that applies dependence graphs to aid object oriented software inspection. Our tool, Coffee Grinder, uses control and data dependence graphs both to immediately visualise a Java system and to facilitate the development of scripts to find defects or locate areas of potential inspection interest. These scripts can output results textually or graphically. We present the design of Coffee Grinder and several example scripts. Coffee Grinder illustrates the case for extensible tool support in the software inspection process

Software Engineers and Engineering: A Survey of Undergraduate Preconceptions

Past research has demonstrated that student misconceptions about degree programs can negatively affect enrolment and retention rates. Software engineering is a relatively new discipline that is distinct from computer science and other engineering specializations; however, it is still rapidly evolving and consequently there is potential for misconceptions about the new discipline to arise. A study was therefore undertaken to investigate the preconceptions of first-year students enrolled in various Bachelor of Engineering degrees. Students were asked to rank the importance of different skills and activities for software engineering, and to rate a variety of statements about software engineering using a Likert scale. First-year preconceptions were compared with the responses of fourth-year software engineering students who had completed a major industry-based project. The two groups of students had statistically significant differences of opinion with respect to many of the survey items. There were no statistically significant differences between the responses of first-year students from different engineering specializations. These findings are discussed in the context of recruiting and retaining software engineering students

Refining 3D models using a two-stage neural network-based iterative process

This paper presents a refinement method that supplements the 3D model construction process. The refinement method addresses the issue of using inaccurate 3D positional information to construct the 3D model. In the context of this paper, the inaccuracies in the 3D information come from a low-cost and low-precision range finder system. The core component of the refinement system is a neural network architecture termed IFOSART that attempts to associate particular corrections to the 3D model given range and intensity information. Results presented show the refinement system successfully reduces the inaccuracies in real-world 3D models.