Fragment-based version management for repositories of business process models

As organizations reach higher levels of Business Process Management maturity, they tend to accumulate large collections of process models. These repositories may contain thousands of activities and be managed by different stakeholders with varying skills and responsibilities. However, while being of great value, these repositories induce high management costs. Thus, it becomes essential to keep track of the various model versions as they may mutually overlap, supersede one another and evolve over time. We propose an innovative versioning model and associated storage structure, specifically designed to maximize sharing across process model versions, and to automatically handle change propagation. The focal point of this technique is to version single process model fragments, rather than entire process models. Indeed empirical evidence shows that real-life process model repositories have numerous duplicate fragments. Experiments on two industrial datasets confirm the usefulness of our technique.

When sparks fly : developing formal mentoring programs for the career development of young and emerging artists

Formal mentoring programs are accepted as a valuable strategy for developing young and emerging artists. This thesis presents the results of an evaluation of the SPARK National Young Artists Mentoring Program (SPARK). SPARK was a ten-month formal mentoring program managed by Youth Arts Queensland (YAQ) on behalf of the Australia Council for the Arts from 2003-2009. The program aimed to assist young and emerging Australian artists between the ages of 18-26 to establish a professional career in the arts. It was a highly successful formal arts mentoring program that facilitated 58 mentorships between young and emerging artists and professional artists from across Australia in five program rounds over its seven year lifespan. Interest from other cultural organisations looking to develop their own formal mentoring programs encouraged YAQ to commission this research to determine how the program works to achieve its effects. This study was conducted with young and emerging artists who participated in SPARK from 2003 to 2008. It took a theory-driven evaluation approach to examine SPARK as an example of what makes formal arts mentoring programs effective. It focused on understanding the program’s theory or how the program worked to achieve its desired outcomes. The program activities and assumed responses to program activities were mapped out in a theories of change model. This theoretical framework was then used to plan the points for data collection. Through the process of data collection, actual program developments were compared to the theoretical framework to see what occurred as expected and what did not. The findings were then generalised for knowledge and wider application. The findings demonstrated that SPARK was a successful and effective program and an exemplar model of a formal mentoring program preparing young and emerging artists for professional careers in the arts. They also indicate several ways in which this already strong program could be further improved, including: looking at the way mentoring relationships are set up and how the mentoring process is managed; considering the balance between artistic and professional development; developing career development competencies and networking skills; taking into account the needs of young and emerging artists to develop their professional identity and build confidence; and giving more thought to the desired program outcomes and considering the issue of timeliness and readiness for career transition. From these findings, together with principles outlined in the mentoring and career development literature, a number of necessary conditions have been identified for developing effective mentoring programs in the career development of young and emerging artists.

Manifolds, patterns and transitions in a creative life

Using sculpture and drawing as my primary methods of investigation, this research explores ways of shifting the emphasis of my creative visual arts practice from object to process whilst still maintaining a primacy of material outcomes. My motivation was to locate ways of developing a sustained practice shaped as much by new works, as by a creative flow between works. I imagined a practice where a logic of structure within discrete forms and a logic of the broader practice might be developed as mutually informed processes. Using basic structural components of multiple wooden curves and linear modes of deployment – in both sculptures and drawings – I have identified both emergence theory and the image of rhizomic growth (Deleuze and Guattari, 1987) as theoretically integral to this imagining of a creative practice, both in terms of critiquing and developing works. Whilst I adopt a formalist approach for this exegesis, the emergence and rhizome models allow it to work as a critique of movement, of becoming and changing, rather than merely a formalism of static structure. In these models, therefore, I have identified a formal approach that can be applied not only to objects, but to practice over time. The thorough reading and application of these ontological models (emergence and rhizome) to visual arts practice, in terms of processes, objects and changes, is the primary contribution of this thesis. The works that form the major component of the research develop, reflect and embody these notions of movement and change.

Strengthening and formally verifying privacy in identity management systems

In a digital world, users’ Personally Identifiable Information (PII) is normally managed with a system called an Identity Management System (IMS). There are many types of IMSs. There are situations when two or more IMSs need to communicate with each other (such as when a service provider needs to obtain some identity information about a user from a trusted identity provider). There could be interoperability issues when communicating parties use different types of IMS. To facilitate interoperability between different IMSs, an Identity Meta System (IMetS) is normally used. An IMetS can, at least theoretically, join various types of IMSs to make them interoperable and give users the illusion that they are interacting with just one IMS. However, due to the complexity of an IMS, attempting to join various types of IMSs is a technically challenging task, let alone assessing how well an IMetS manages to integrate these IMSs. The first contribution of this thesis is the development of a generic IMS model called the Layered Identity Infrastructure Model (LIIM). Using this model, we develop a set of properties that an ideal IMetS should provide. This idealized form is then used as a benchmark to evaluate existing IMetSs. Different types of IMS provide varying levels of privacy protection support. Unfortunately, as observed by Jøsang et al (2007), there is insufficient privacy protection in many of the existing IMSs. In this thesis, we study and extend a type of privacy enhancing technology known as an Anonymous Credential System (ACS). In particular, we extend the ACS which is built on the cryptographic primitives proposed by Camenisch, Lysyanskaya, and Shoup. We call this system the Camenisch, Lysyanskaya, Shoup - Anonymous Credential System (CLS-ACS). The goal of CLS-ACS is to let users be as anonymous as possible. Unfortunately, CLS-ACS has problems, including (1) the concentration of power to a single entity - known as the Anonymity Revocation Manager (ARM) - who, if malicious, can trivially reveal a user’s PII (resulting in an illegal revocation of the user’s anonymity), and (2) poor performance due to the resource-intensive cryptographic operations required. The second and third contributions of this thesis are the proposal of two protocols that reduce the trust dependencies on the ARM during users’ anonymity revocation. Both protocols distribute trust from the ARM to a set of n referees (n > 1), resulting in a significant reduction of the probability of an anonymity revocation being performed illegally. The first protocol, called the User Centric Anonymity Revocation Protocol (UCARP), allows a user’s anonymity to be revoked in a user-centric manner (that is, the user is aware that his/her anonymity is about to be revoked). The second protocol, called the Anonymity Revocation Protocol with Re-encryption (ARPR), allows a user’s anonymity to be revoked by a service provider in an accountable manner (that is, there is a clear mechanism to determine which entity who can eventually learn - and possibly misuse - the identity of the user). The fourth contribution of this thesis is the proposal of a protocol called the Private Information Escrow bound to Multiple Conditions Protocol (PIEMCP). This protocol is designed to address the performance issue of CLS-ACS by applying the CLS-ACS in a federated single sign-on (FSSO) environment. Our analysis shows that PIEMCP can both reduce the amount of expensive modular exponentiation operations required and lower the risk of illegal revocation of users’ anonymity. Finally, the protocols proposed in this thesis are complex and need to be formally evaluated to ensure that their required security properties are satisfied. In this thesis, we use Coloured Petri nets (CPNs) and its corresponding state space analysis techniques. All of the protocols proposed in this thesis have been formally modeled and verified using these formal techniques. Therefore, the fifth contribution of this thesis is a demonstration of the applicability of CPN and its corresponding analysis techniques in modeling and verifying privacy enhancing protocols. To our knowledge, this is the first time that CPN has been comprehensively applied to model and verify privacy enhancing protocols. From our experience, we also propose several CPN modeling approaches, including complex cryptographic primitives (such as zero-knowledge proof protocol) modeling, attack parameterization, and others. The proposed approaches can be applied to other security protocols, not just privacy enhancing protocols.

Models of collective cell spreading with variable cell aspect ratio : a motivation for degenerate diffusion models

Continuum diffusion models are often used to represent the collective motion of cell populations. Most previous studies have simply used linear diffusion to represent collective cell spreading, while others found that degenerate nonlinear diffusion provides a better match to experimental cell density profiles. In the cell modeling literature there is no guidance available with regard to which approach is more appropriate for representing the spreading of cell populations. Furthermore, there is no knowledge of particular experimental measurements that can be made to distinguish between situations where these two models are appropriate. Here we provide a link between individual-based and continuum models using a multi-scale approach in which we analyze the collective motion of a population of interacting agents in a generalized lattice-based exclusion process. For round agents that occupy a single lattice site, we find that the relevant continuum description of the system is a linear diffusion equation, whereas for elongated rod-shaped agents that occupy L adjacent lattice sites we find that the relevant continuum description is connected to the porous media equation (pme). The exponent in the nonlinear diffusivity function is related to the aspect ratio of the agents. Our work provides a physical connection between modeling collective cell spreading and the use of either the linear diffusion equation or the pme to represent cell density profiles. Results suggest that when using continuum models to represent cell population spreading, we should take care to account for variations in the cell aspect ratio because different aspect ratios lead to different continuum models.

American public journalism versus other international media models

Chapter 2 of 'International Journalism and Democracy' provides examples of what the author dubs "deliberative journalism". Following a definition of deliberative journalism in Chapter 1, the book's second chapter examines major models of deliberative journalism that are in operation around the world. These models include public journalism, citizen journalism, community and alternative media, development journalism and peace journalism. The author argues that when these new forms of journalism are practiced well, they extend people's ability to identify, express, understand and respond to politics and issues affecting their communities. However, the main models of deliberative journalism all have contentious elements. Many deliberative journalism practioners have been subjected to criticism for lack of objectivity and poor professional standards. Many of their activities have clearly been ill-conceived. The author also finds that neither professional nor citizen journalists have a strong understanding of what constitutes "good practice" in deliberative journalism. Furthermore, there is much debate as to whether the type of "citizen journalism" that is posted intermittently on Facebook, Twitter, blogs and other social media can even be defined as "journalism". The practice of deliberative journalism can potentially contribute to public deliberation, but it does not always do so in any immediate or obvious way. The author finds that even so, deliberative journalism indirectly strengthens the environments that support fertile deliberation and decision making. (See the Extended Abstract for further details.)

Where money and meanings meet : theorizing the emergence of new values in media and education

Recent developments in technology, globalization, and consumer activism have challenged the "broadcasting model" of natonally bounded, vertically integrated, monopolistic, expert-paradigm media industries, dedicated to supplying leisure entertainment to more or less passive consumers. Instead, attention has turned to globally traded formats, social network markets, consumer-created content, multiplatform "publication," and a semiotic long tail where niche representations can be as valuable as blockbusters. Such chenges are just as much a challenge to education as they are to business models. And education, both formal and informal, is a dynamic agent in these processes, participation, and creative content require a rethink of "studies" just as much as of "media."

Homo nuntius - messaging humanity

This article analyzes the history of the term "the message" in communication, cultural, and media studies. It goes on to propose that conceptual coherence can only be achieved for this concept if it is considered historically and in evolutionary terms. The article then pursues recent changes in the status of "the message" through 4 phases of semiotic history - (1) the representative (modern), (2) the excessive (postmodern), (3) the productive (user-created), and (4) the message as human identity- Homo nuntius. Having arrived at a conceptualization of 'messaging' as constitutive of our species, the final section provides the example of fashion communication to show what is meant by the term "Homo nuntius - messaging humanity".

Years 2 to 6 students' ability to generalise : models, representations and theory for teaching and learning

Over the last three years, in our Early Algebra Thinking Project, we have been studying Years 3 to 5 students’ ability to generalise in a variety of situations, namely, compensation principles in computation, the balance principle in equivalence and equations, change and inverse change rules with function machines, and pattern rules with growing patterns. In these studies, we have attempted to involve a variety of models and representations and to build students’ abilities to switch between them (in line with the theories of Dreyfus, 1991, and Duval, 1999). The results have shown the negative effect of closure on generalisation in symbolic representations, the predominance of single variance generalisation over covariant generalisation in tabular representations, and the reduced ability to readily identify commonalities and relationships in enactive and iconic representations. This chapter uses the results to explore the interrelation between generalisation and verbal and visual comprehension of context. The studies evidence the importance of understanding and communicating aspects of representational forms which allowed commonalities to be seen across or between representations. Finally the chapter explores the implications of the studies for a theory that describes a growth in integration of models and representations that leads to generalisation.

How do consumers react to physically larger models? Effects of model body size, weight control beliefs and product type on evaluations and body perceptions

The purpose of this article is to examine how a consumer’s weight control beliefs (WCB), a female advertising model’s body size (slim or large) and product type influence consumer evaluations and consumer body perceptions. The study uses an experiment of 371 consumers. The design of the experiment was a 2 (weight control belief: internal, external) X 2 (model size: larger sized, slim) X 2 (product type: weight controlling, non-weight controlling) between-participants factorial design. Results reveal two key contributions. First, larger sized models result in consumers feeling less pressure from society to be thin, viewing their actual shape as slimmer relative to viewing a slim model and wanting a thinner ideal body shape. Slim models result in the opposite effects. Second this research reveals a boundary condition for the extent to which endorser–product congruency theory can be generalized to endorsers of a larger body size. Results indicate that consumer WCB may be a useful variable to consider when marketers consider the use of larger models in advertising.

International journalism and democracy : civic engagement models from around the world

"International Journalism and Democracy" explores a new form of journalism that has been dubbed ‘deliberative journalism’. As the name suggests, these forms of journalism support deliberation — the processes in which citizens recognize and discuss the issues that affect their communities, appraise the potential responses to those issues, and make decisions about whether and how to take action. Authors from across the globe identify the types of journalism that assist deliberative politics in different cultural and political contexts. Case studies from 15 nations spotlight different approaches to deliberative journalism, including strategies that have been sometimes been labeled as public or civic journalism, peace journalism, development journalism, citizen journalism, the street press, community journalism, social entrepreneurism, or other names. Countries that are studied in-depth include the United States, the United Kingdom, Germany, Finland, China, India, Japan, Indonesia, Australia, New Zealand, South Africa, Nigeria, Brazil, Colombia and Puerto Rico. Each of the approaches that are described offers a distinctive potential to support deliberative democracy. However, the book does not present any of these models or case studies as examples of categorical success. Instead, it explores different elements of the nature, strengths, limitations and challenges of each approach, as well as issues affecting their longer-term sustainability and effectiveness. The book also describes the underlying principles of deliberation, the media’s potential role in deliberation from a theoretical and practical perspective, and ongoing issues for deliberative media practitioners.

Conceptual models of satisfaction level in construction

It is recognized that, in general, the performance of construction projects does not meet optimal expectations. One aspect of this is the performance of each participant, which is interdependent and makes a significance impact on overall project outcomes. Of these, the client is traditionally the owner of the project, the architect or engineer is engaged as the lead designer and a contractor is selected to construct the facilities. Generally, the performance of the participants is gauged by considering three main factors, namely time, cost and quality. As the level of satisfaction is a subjective measurement, it is rarely used in the performance evaluation of construction work. Recently, various approaches to the measurement of satisfaction have been made in attempting to determine the performance of construction project outcomes – for instance client satisfaction, consultant satisfaction, contractor satisfaction, customer satisfaction and home buyer satisfaction. These not only identify the performance of the construction project, but are also used to improve and maintain relationships. In addition, these assessments are necessary for continuous improvement and enhanced cooperation between participants. The measurement of satisfaction levels primarily involves expectations and perceptions. An expectation can be regarded as a comparison standard of different needs, motives and beliefs, while a perception is a subjective interpretation that is influenced by moods, experiences and values. This suggests that the disparity between perceptions and expectations may be used to represent different levels of satisfaction. However, this concept is rather new and in need of further investigation. This paper examines the current methods commonly practiced in measuring satisfaction level and the advantages of promoting these methods. The results provided are a preliminary review of the advantages of satisfaction measurement in the construction industry and recommendations are made concerning the most appropriate methods for use in identifying the performance of project outcomes.

Expertise in software design : novice and expert models

This paper investigates how software designers use their knowledge during the design process. The research is based on the analysis of the observational and verbal data from three software design teams generated during the conceptual stage of the design process. The knowledge captured from the analysis of the mapped design team data is utilized to generate descriptive models of novice and expert designers. These models contribute to a better understanding of the connections between, and integration of, designer variables, and to a better understanding of software design expertise and its development. The models are transferable to other domains.