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While studying Test-First Development (TFD), researchers have typically com- pared it to Test-Last Development (TLD), across groups or projects, and for relatively short durations. But, we have observed that teams testing fine-grained changes do not necessarily develop tests for those changes first. And, comparing across groups or projects is difficult, due to the "contextual variables" specific to each. Finally, many "real-life" projects have long durations. Because of TFD's potential to increase team speed or product quality, and because of these previous limitations, we were motivated to design and execute our own related study. Our work on this study has resulted in three original con- tributions to knowledge: (1) our software change model; (2) our measurement method; and (3) our study results. First, as part of our software model, we defined Test-With Development (TWD) as more general than TFD, and as a step that can be practised to a degree. Then, we defined team speed measures for a developer's product change: initial net size, discards over time, and net size over time. As well, we adopted product quality measures for a developer's product change: change in the number of potential bugs and change in the average method complexity. Second, we defined a measurement method which allowed us to perform two studies, across six open-source projects and thousands of developer changes. With it, we performed an auxiliary study to calibrate our discards over time measure. Then, we used it to perform our main study to compare the effects of TWD product changes on some attributes of team speed and product quality. 2 3 Finally, the results from our main study indicate that there were significant differences between the effects of TWD product changes. We interpret these results to indicate that teams that practice TWD can increase their efficiency, by reducing their product's complexity faster.

This thesis will investigate the concept of agile manufacturing as it applies to the mature traditional pottery manufacturing industry of Stoke-on- Trent. This thesis has two research objectives the first is to examine whether the theory of agility fully informs the actual practice of agility and agile manufacture and, secondly, the thesis looks into the gap between the rhetoric of agility (what they say they do) and the practice of agility (what they actually do). The thesis uses a critical realist approach in attempting to locate the essence of "agility" as what some have called a "new" productive regime (laccoca Institute, 1991), with the aim of identifying what role it can play in re-structuring sub-optimal forms of productive organisation within the Stoke-on-Trent ceramic industry. In order to clarify the basis of this argument agility is broadly defined as "the ability of an organisation to thrive in a constantly changing, unpredictable business environment" (laccoca Institute, 1991). The broadness of this type of definition is part of the intuitive appeal of this form of productive regime. The thesis shows that when considering agility in this context that there exists many and varied complexities within organisations and between organisations that the model does not take into account. Therefore agility should not be treated as a panacea for the manufacturing strategy of the case companies studied. Previous research had failed to provide any linkages between agility and wider debates relating to productive and organisational change. Existing research has its bias towards researching a limited set of industries such as automotive and food production, where manufacturers are assemblers often hold pivotal roles in the supply chain. Agility attempts to provide guidance about 'managing' physical and social relationships within and between companies in response to growing market complexity, yet tends to have an under socialised view of these types of interactions. This tendency reduces interaction and human aspects to simple unidirectional cause and effect. These theories therefore do not take into account the more subjective aspects of interaction. This is especially important within the Stoke-on- Trent ceramics industry that is a mature, geographically clustered manufacturing area.

The potential global consequences of rates of resource consumption in modern economies have prompted several governments to use forms of voluntary regulation to promote improved resource efficiency within the firm. The UK government outsourced a wide programme to encourage waste minimisation. Part of this promoted local 'waste minimisation clubs' (now called resource efficiency clubs) which worked with members to achieve simultaneous reductions in materials and energy use, and in costs. More than 80 were run. Typically, intermediaries (some from universities) helped establish local partnerships, grant funding was obtained, volunteer firms participated, and activity ceased when funding did. Some results were inspiring and cited in policy documents. Yet it was hard to recruit and few published reports. This thesis focuses on the intermediaries. It examines their insecure and sometimes contentious positions, their claims-making and bricolage, and their abilities to shape communications about, and arrangements within, such best practice projects. Previously, intermediaries have been almost invisible participants in these temporary 'project worlds' where change is constantly recommended. Using constructs from institutionalist theory to study activity relating to short-term initiatives is unusual and 'stretches' the theory to its very edges. Yet interorganizational projects are now common and reflect what W. W. Powell (2001:30) calls "a new logic of organizing," involving, in his terms, profoundly new and discontinuous approaches to mechanisms of governance, creating disturbances at the boundaries of organizations and to the status order of organizational fields. The final chapters suggest ways of conceptualising the intermediaries' roles within institutionalist theory and consider their significance in voluntary regulation. One suggestion likens them to commensals, operating between fields of formal organizations, proffering various fashionable services related to norms, translating ideas more or less well, and constituting a mere potentiality for change, whilst reinforcing certain expectations. The thesis ends with suggestions for further research.

Most organisations are working hard to improve their performance and to achieve competitive advantage over their rivals. They may accomplish these ambitions through carrying out their business processes more effectively. Hence it is important to consider such processes and look for ways in which they can be improved. Any organisational business process encompasses several elements that interact and collaborate with each other to achieve the required objectives. These elements can be classified into hard aspects, which deal with tangible issues related to the software system or the technology in general, and soft aspects, which deal with issues related to the human part of the business process. If the business process needs to be analysed and redesigned to improve its performance, it is important to use a suitable approach or intervention that takes into account all of these elements. This thesis proposes an approach to investigate organisational business processes by considering both soft and hard aspects. The approach, Soft Workflow Modelling (SWfM), is developed as a result of reviewing several workflow products and models using a developed workflow perspectives framework which involves several perspectives covering the soft and hard aspects of the workflow system. The SWfM approach models the organisational business process as a workflow system by handling the various perspectives of the workflow perspectives framework. This approach combines the Soft Systems Methodology (SSM) with the Unified Modelling Language (UML), as a standard modelling language of the object-oriented paradigm. The basic framework adopted is that of SSM with the inclusion of UML diagrams and techniques to deal with the aspects that SSM cannot handle. The approach also supports SSM by providing a developed tool to assist in constructing a conceptual model which is considered as the basis to model the workflow system. A case study is developed for illustrative purposes.

"Operational effectiveness" is the means by which market leading value propositions are delivered to customers. The contribution of "operational effectiveness" in manufacturing to competitive strategy has been established. The "operational effectiveness" approach has been based on scientific reductionism, defining itself by list of "best practice" tools, techniques and philosophies. This thesis argues that this had led to loss of the "operational effectiveness" whole, causing variegated success in application of these tools. Complex systems SCience, with its origins in communications, control theory and non-linear dynamical systems, has provided previously unavailable insight into real-world systems. The applications to date in manufacturing have been in soft systems appearing either as metaphors or computationally difficult optimisation-type problems. This thesis argues that manufacturing companies are complex systems. As a result measures for complex behaviour and structure in these systems will yield fresh insight currently unavailable through the reductionist worldview of "operational effectiveness". This research proposes a new framework of agents that connects the "operational effective" and complex systems views, without the loss of system richness of the complexity worldview. This framework comprises interrelated sets of input/output Entities, produced through Activities carried out by Resources. Novel measures of flow efficacy and the structure of these set-based relationships are then obtained based on this common framework by the use of Entropy and QanalYSis respectively. A methodology for the creation of the framework, its measurement and validation is then proposed and tested. Three case studies have been carried out in the actual processes of a manufacturing company. The studies have been able to show a consistent benefit from the use of complexity-based measures over and above what would have been available from "operational effectiveness Correlation and independence have been observed in the concurrent use of both complexity measures on the frameworks, demonstrating their independence and interdependence.

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Τα σύγχρονα συστήματα παραγωγής πρέπει να λειτουργούν αποδοτικά σε ένα δυναμικά μεταβαλλόμενο περιβάλλον. Ένα βασικό χαρακτηριστικό που πρέπει να λάβουν υπόψη τους οι μηχανικοί στη βιομηχανία είναι η ευελιξία των συστημάτων παραγωγής. Η ευελιξία αναφέρεται στην ικανότητα ενός συστήματος παραγωγής να ανταποκρίνεται και να προσαρμόζεται στις αλλαγές του περιβάλλοντος στο οποίο λειτουργεί. Αλλά η ευελιξία είναι δύσκολο να συμπεριληφθεί στη διαδικασία λήψης αποφάσεων κατά τον σχεδιασμό ή τη λειτουργία ενός συστήματος, αν δεν έχει περιγραφεί ποσοτικά. Ο σκοπός αυτής της διατριβής είναι να αναπτύξει και να επιδείξει μια μέθοδο για την εκτίμηση και ποσοτικοποίηση της ευελιξίας. Η μέθοδος μπορεί να χρησιμοποιηθεί σε πραγματικά προβλήματα στη βιομηχανία και να βοηθήση στη λήψη αποφάσεων σχετικά με τον απαραίτητο βαθμό της ευελιξίας που πρέπει να έχει ένα σύστημα παραγωγής ειδικά στην περίπτωση που υπάρχει αβεβαιότητα και είναι δύσκολο να γίνουν αξιόπιστες προβλέψεις σχετικά με τις απαιτήσεις της αγοράς. Στην διεθνή επιστημονική βιβλιογραφία έχουν καταγραφεί αρκετές εργασίες που προσεγγίζουν το πρόβλημα της εκτίμησης της ευελιξίας ενός συστήματος παραγωγής. Οι περισσότερες όμως από τις εργασίες αντιμετωπίζουν μεμονωμένα προβλήματα, κάτω από ειδικές συνθήκες, που τις περισσότερες φορές αναφέρονται και σε συγκεκριμένους τύπους συστημάτων παραγωγής. Η προτεινόμενη μέθοδος στηρίζεται στη θεώρηση ότι η ευελιξία ενός συστήματος παραγωγής καθορίζεται από την ευαισθησία του στις αλλαγές. Όσο λιγότερο ευαίσθητο ένα σύστημα είναι στις αλλαγές του περιβάλλοντος στο οποίο λειτουργεί τόσο περισσότερο ευέλικτο είναι. Η βασική αυτή θεώρηση εφαρμόζεται μέσω της μέτρησης του εύρους των διαφόρων τιμών του συνολικού κόστους ενός συστήματος παραγωγής. Οι τιμές του συνολικού κόστους υπολογίζεται για καθένα σενάριο από ένα μεγάλο αριθμό πιθανών σεναρίων αγοράς. Στη συνέχεια με στατιστική ανάλυση στις τιμές του συνολικού κόστους οδηγούμαστε σε συμπεράσματα για την ευαισθησία ενός συστήματος παραγωγής σε ένα αβέβαιο περιβάλλον λειτουργίας. Ο υπολογισμός του συνολικού κόστους λαμβάνει υπόψη του διάφορες φάσεις του συστήματος παραγωγής στον κύκλο ζωής του όπως την αρχική επένδυση και το κόστος των αλλαγών. Επιπλέον, για να μπορούν οι διαφορετικές τιμές του κόστους να είναι συγκρίσιμες θα πρέπει να υπολογιστούν με βάση κάποιον κανόνα. Η εργασία αυτή προτείνει έναν τρόπο για την εύρεση του ελάχιστου κόστους στον κύκλο ζωής ενός συστήματος παραγωγής. Η προτεινόμενη μέθοδος εφαρμόζεται σε μια περίπτωση μελέτης στην αυτοκινητοβιομηχανία και τέλος περιγράφεται ένα λογισμικό που υλοποιεί την προτεινόμενη μέθοδο καθώς και η UML (Unified Modelling Language) περιγραφή των βασικών οντοτήτων. / Modern manufacturing firms must learn to operate effectively in very dynamic environments. One key aspect that firms must consider is manufacturing flexibility. Manufacturing flexibility refers to the ability of a manufacturing system to accommodate uncertainty in the production environment. But flexibility cannot be considered in the decision making process if it is not assessed in quantifiable terms. The goal of this dissertation is to develop and demonstrate a practical method to assist manufacturers in managing environmental uncertainty and in determining the appropriate level of flexibility in their production systems. A number of research efforts have been published in the litterature that deal with the scientific issue of flexibility assessment. However, most of the published research work deals with case specific engineering problems, under certain circumstances, and in most of the cases they are applicable to specific types of production system. The approach suggested by the this dissertation considers that manufacturing flexibility is determined by its sensitivity to changes. The less flexible a manufacturing system is the more flexible it should be considered. We consider flexibility during the lifecycle of a system, from initial investment to major reconfiguration. A large number of market scenarios are being considered and the lifecycle cost of the system for all scenarios is calculated. Following, statistical analysis on the lifecycle cost results provides results on the sensitivity of the system to the uncertainty of the market environment. Furthermore, in order to make the lifecycle cost values comparable amongst the different production systems, their minimum value is calculated at a minimum level with the help of a specially developed optimization algorithm. The proposed method is applied in a case study in the automotive industry. Finally, a web-based software package that implements the proposed method along with the UML (Unified Modelling Language) description of the main entities is also being described.

Ο στόχος αυτής της μελέτης είναι να μετρηθεί η αποδοτικότητα των επαγγελματικών ομάδων ποδοσφαίρου που παίζουν στην Σούπερ Λίγκα, την πρώτη κατηγορία στην Ελλάδα, κατά τη μετατροπή των επιθετικών τους κινήσεων σε αθλητική επιτυχία στη διάρκεια του αγώνα. Ο χρονικός ορίζοντας της μελέτης είναι οι τρεις περίοδοι από το 2004 έως το 2007. Με αυτό το στόχο η γράφουσα εφάρμοσε τη μεθοδολογία περιβάλλουσας ανάλυσης δεδομένων (DEA). Το κύριο συμπέρασμα της εργασίας είναι ότι οι αποδοτικές ομάδες στη δραστηριότητα που αναλύεται δεν αντιστοιχούν πάντα με εκείνες που τερμάτισαν υψηλότερα στην κατηγορία στο τέλος της αγωνιστικής περιόδου. / The aim of this study is to measure the efficiency of the professional soccer teams that play in the Greek Super Leaugue. The timeline of the study is the three seasons from 2004 to 2007. To that end, the writer used the data envelopment analysis methodology (DEA). The main conclusion is that the efficient teams in the activity analyzed do not always correspond with those that finished highest in the league at the end of the season.