Exploring the Software Verification and Validation Process with Focus on Efficient Fault Detection

Quality is an aspect of high importance in software development projects. The software organizations have to ensure that the quality of their developed products is what the customers expect. Thus, the organizations have to verify that the product is functioning as expected and validate that the product is what the customers expect. Empirical studies have shown that in many software development projects as much as half of the projected schedule is spent on the verification and validation activities. The research in this thesis focuses on exploring the state of practice of the verification and validation process and investigating methods for achieving efficient fault detection during the software development. The thesis aims at increasing the understanding of the activities conducted to verify and validate the software products, by the means of empirical research in the software engineering domain. A survey of eleven Swedish software development organizations investigates the current state of practice of the verification and validation activities, and how these activities are managed today. The need for communicating and visualising the verification and validation process was expressed during the survey. Therefore the usefulness of process simulations was evaluated in the thesis. The simulations increased the understanding of the relationships between different activities among the involved participants. In addition, an experiment was conducted to compare the performance of the two verification and validation activities, inspection and testing. In the future work, empirical research, including experiment results, will be used for calibration and validation of simulation models, with focus on using simulation as a method for decision support in the verification and validation process

Process models in design and development

© 2017 The Author(s) Many models of the design and development process have been published over the years, representing it for different purposes and from different points of view. This article contributes an organising framework that clarifies the topology of the literature on these models and thereby relates the main perspectives that have been developed. The main categories of model are introduced. Their contexts, advantages, and limitations are considered through discussion of selected examples. It is demonstrated that the framework integrates coverage of earlier reviews and as such provides a new perspective on the literature. Finally, key characteristics of design and development process models are discussed considering their applications in practice, and opportunities for further research are suggested. Overall, the article should aid researchers in positioning new models and new modelling approaches in relation to state-of-the-art. It may also be of interest to practitioners and educators seeking an overview of developments in this area

Shall we play a game?

In response to real and perceived short-comings in the quality and productivity of software engineering practices and projects, professionally-endorsed graduate and post-graduate curriculum guides have been developed to meet evolving technical developments and industry demands. Each of these curriculum guidelines identifies better software engineering management skills and soft, peopleware skills as critical for all graduating students, but they provide little guidance on how to achieve this. One possible way is to use a serious game — a game designed to educate players about some of the dynamic complexities of the field in a safe and inexpensive environment. This thesis presents the results of a qualitative research project that used a simple game of a software project to see if and how games could contribute to better software project management education; and if they could, then what features and attributes made them most efficacious. That is, shall we— should we— play games in software engineering management? The primary research tool for this project was a game called Simsoft. Physically, Simsoft comes in two pieces. There is an A0-sized printed game board around which the players gather to discuss the current state of their project and to consider their next move. The board shows the flow of the game while plastic counters are used to represent the staff of the project. Poker chips represent the team’s budget, with which they can purchase more staff, and from which certain game events may draw or reimburse amounts depending on decisions made during the course of the game. There is also a simple Java-based dashboard, through which the players can see the current and historical state of the project in a series of reports and messages; and they can adjust the project’s settings. The engine behind Simsoft is a system dynamics model which embodies the fundamental causal relationships of simple software development projects. In Simsoft game sessions, teams of students, and practicing project managers and software engineers managed a hypothetical software development project with the aim of completing the project on time and within budget (with poker chips left over). Based on the starting scenario of the game, information provided during the game, and their own real-world experience, the players made decisions about how to proceed— whether to hire more staff or reduce the number, what hours should be worked, and so on. After each decision set had been entered, the game was run for another next time period, (a week, a month, or a quarter). The game was now in a new state which the players had to interpret from the game board and decide how to proceed. The findings showed that games can contribute to better software engineering management education and help bridge the pedagogical gaps in current curriculum guidelines. However, they can’t do this by themselves and for best effect they should be used in conjunction with other pedagogical tools. The findings also showed that simple games and games in which the players are able to relate the game world to an external context are the most efficacious

Feedback systems in the design and development process

Feedback is essential in the design and development process, occurring in the generation of new designs, in the adaptation of development projects to emerging information, and in coordination and collaboration of project participants—among many other aspects. Feedback also contributes to development project complexity and may cause resistance to desirable changes. But despite the importance of feedback in the design and development process (DDP), relatively few publications have examined this topic in an integrated way. This article makes two contributions towards addressing the gap. First, a conceptual framework is developed to organise perspectives on feedback in the DDP literature. The framework shows how feedback occurs at different levels of the design and development process and how it affects important DDP behaviours, namely goal-seeking, learning and emergence. Second, a system-theoretic model of feedback situations in the design and development process is introduced to synthesise key ideas. We provide concrete examples to show how this new model can be used to frame DDP situations and draw out feedback-related insight

Modelling and simulation of paradigms for printed circuit board assembly to support the UK's competency in high reliability electronics

The fundamental requirement of the research reported within this thesis is the provision of physical models to enable model based simulation of mainstream printed circuit assembly (PCA) process discrete events for use within to-be-developed (or under development) software tools which codify cause & effects knowledge for use in product and process design optimisation. To support a national competitive advantage in high reliability electronics UK based producers of aircraft electronic subsystems require advanced simulation tools which offer model based guidance. In turn, maximization of manufacturability and minimization of uncontrolled rework must therefore enhance inservice sustainability for ‘power-by-the-hour’ commercial aircraft operation business models. [Continues.

Lean Product Development process structure and its effect on the performance of NPD projects

New product development (NPD) has a pivotal role in the industrial competition, and makes a basis for long‐term prosperity of companies. To survive in today's fast‐changing market environment, companies are always trying to improve the performance of their NPD projects, by implementing new approaches, such as Lean Product Development (LPD). Nevertheless, applying such approaches is not straightforward, mainly due to the high level of interdependency between development activities and the role of dynamic effects in the project performance. Understanding the combined effects of dynamic features, including feedback loops, time delays and nonlinear causal relationships, is the main step for achieving higher project performance. In this thesis, the dynamics of LPD process structure is investigated to find the ways it could affect the time, cost and quality performance of a development project. As there is no consensus about the definition of LPD among researchers in this filed, first through a comprehensive literature review different approaches to LPD are studied. Two major approaches for LPD are introduced based on the adaptation of lean manufacturing tools and techniques for optimizing NPD processes, or extracting LPD specific tools and techniques from Toyota Product Development System (TPDS). The second approach is proved to be more applicable, mainly due to fundamental differences between manufacturing and NPD environments, and the LPD process design based on TPDS is selected as the focal point for this research. The combination of Set‐Based approach to design and Concurrent Engineering in the form of SBCE is identified as the unique feature of LPD process structure which have been the topic of several researches in this field during past decade. Set‐based design approach calls for the higher number of iteration cycles at the front end of the projects, and is responsible for higher project effectiveness while increases the time and effort invested. On the other hand, concurrent engineering targets the project duration, and is an efficiency factor, but if not structured properly it could have an opposite effect through increasing the number of rework cycles. Although the performance of TPDS which is the best benchmark for LPD shows the positive effect of SBCE on the projects performance, the reasons behind it and the way through which two approaches could be structured to achieve the favourable results is not clear yet. In addition, while different types of new product development projects, based on VII their levels of complexity and innovation, are defined and executed in companies, it is not clear if SBCE approach has the same impact on all project types. To investigate the reasons behind the superiority of SBCE and its effects in different types of development projects the systems thinking approach is selected as the main research methodology to provide a holistic view on the development projects through looking on interdependencies between performance measures and process structure. System dynamics modelling is used as the research method, due to its capacity in modelling feedback loops and iteration and rework cycles, as underlying factors which determine the time, cost and quality performance in projects. The model is built based on verified structures for rework cycle and resource allocation as the platform for the model, and becomes more specific for the purpose of this research by adding structures related to the iteration cycles, number of initial concepts, and effect of project type. After passing the standard system dynamics validation tests, the model is calibrated using the historical project data from different projects in a major car manufacturing company. The calibrated and verified model then used for the policy analysis by defining different scenarios based on the number of iteration cycles during the conceptual design phase, number of initial concepts and the type of project. All types of projects show the improved performance metrics when moving towards the SBCE approach by increasing the number of iteration cycle. However, the degree of improvement for projects with higher levels of complexity is more profound. In addition, it is concluded for projects with the high level of complexity that increasing the number of initial concepts has the positive effect on all project performance measures. This research results have a methodological contribution by providing a method for rigorous representation of the impact of LPD process structure on projects performance through simulation. From the practical point of view, the developed model could be used by project managers as a guide for making informed decisions which guarantee the long‐term success of development projects

The Development of Methods to Estimate and Reduce Design Rework

Design rework includes unnecessary repetition in design tasks to correct design problems. Resolving design matters in advance, through in-depth understanding of the design planning and rework issues and development of effective predictive tools could contribute to higher business profit margins and a faster product time-to-market. This research aims to develop three novel and structured methods to predict the design rework occurrence and effort at the very early design stage, which may otherwise remain undiscovered until the testing and refinement phase. The major contribution obtained from the Design Rework Probability of Occurrence Estimation method, DRePOE, is the development of design rework drivers. The developed drivers have been synthesised with data from interview results, direct observations, and archival records obtained from eleven world-class aerospace and automotive components manufacturers. To predict the probability of occurrence, the individual score of each driver was compared against historical records utilising the analogy-based method. The Design Rework Effort Estimation method, DREE, was developed to interconnect functional structures and identify failure relationships among components. A significant contribution of The DREE method is its capability to assess the design rework effort at the component level under the worst-case scenario. Next a Prioritisation Design by Design Rework Effort Based method, PriDDREB, was developed to provide a tool to forecast the maximum design rework given the constraint. This method provides a tool to determine and prioritise the components that may require a significant design rework effort. The three methods developed were validated with an automotive water pump, a turbocharger, and a McPherson strut suspension system in accordance with the validation square method. It is demonstrated that DRePOE, DREE, PriDDREB methods can offer the product design team a means to predict the probability of design rework occurrence and assess the required effort during the testing and refinement phase at the very early design phase