Strong designated verifier signature in a multi-user setting

The security of strong designated verifier (SDV) signature schemes has thus far been analyzed only in a two-user setting. We observe that security in a two-user setting does not necessarily imply the same in a multi-user setting for SDV signatures. Moreover, we show that existing security notions do not adequately model the security of SDV signatures even in a two-user setting. We then propose revised notions of security in a multi-user setting and show that no existing scheme satisfies these notions. A new SDV signature scheme is then presented and proven secure under the revised notions in the standard model. For the purpose of constructing the SDV signature scheme, we propose a one-pass key establishment protocol in the standard model, which is of independent interest in itself.

User-designer collaboration during the early stage of the product development process

As an understanding of users' tacit knowledge and latent needs embedded in user experience has played a critical role in product development, users’ direct involvement in design has become a necessary part of the design process. Various ways of accessing users' tacit knowledge and latent needs have been explored in the field of user-centred design, participatory design, and design for experiencing. User-designer collaboration has been used unconsciously by traditional designers to facilitate the transfer of users' tacit knowledge and to elicit new knowledge. However, what makes user-designer collaboration an effective strategy has rarely been reported on or explored. Therefore, interaction patterns between the users and the designers in three industry-supported user involvement cases were studied. In order to develop a coding system, collaboration was defined as a set of coordinated and joint problem solving activities, measured by the elicitation of new knowledge from collaboration. The analysis of interaction patterns in the user involvement cases revealed that allowing users to challenge or modify their contextual experiences facilitates the transfer of knowledge and new knowledge generation. It was concluded that users can be more effectively integrated into the product development process by employing collaboration strategies to intensify the depth of user involvement.

Empowerment games : empathic design probes for user participation in community housing

This paper documents the empowering process of a group of public housing residents through different design probing exercises. These exercises worked along with existing social processes without any involvement of designers. This paper shows how a design researcher devised a series of probing tools called "empowerment games" with a group of active users. These games are self-learning tools for making the abstract language of design legible to users. The main purpose of this intitiative was to change the preconception of govenmental bodies and professional designers of the passivity of the users with regard to their designed environment. This was the first case of the application of a participatory design process in Hong Kong subsidized housing. Design empathy is a central skill when working with users throughout the whole design research project.

User friendly guide for rehabilitation or strengthening of bridge structures using fiber reinforced polymer composites

A worldwide interest is being generated in the use of fibre reinforced polymer composites (FRP) in rehabilitation of reinforced concrete structures. As a replacement for the traditional steel plates or external post-tensioning in strengthening applications, various types of FRP plates, with their high strength to weight ratio and good resistance to corrosion, represent a class of ideal material in external retrofitting. Within the last ten years, many design guidelines have been published to provide guidance for the selection, design and installation of FRP systems for external strengthening of concrete structures. Use of these guidelines requires understanding of a number of issues pertaining to different properties and structural failure modes specific to these materials. A research initiative funded by the CRC for Construction Innovation was undertaken (primarily at RMIT) to develop a decision support tool and a user friendly guide for use of fibre reinforced polymer composites in rehabilitation of concrete structures. The user guidelines presented in this report were developed after industry consultation and a comprehensive review of the state of the art technology. The scope of the guide was mainly developed based on outcomes of two workshops with Queensland Department of Main Roads (QDMR). The document covers material properties, recommended construction requirements, design philosophy, flexural, shear and torsional strengthening of beams and strengthening of columns. In developing this document, the guidelines published on FIB Bulletin 14 (2002), Task group 9.3, International Federation of Structural Concrete (FIB) and American Concrete Institute Committee 440 report (2002) were consulted in conjunction with provisions of the Austroads Bridge design code (1992) and Australian Concrete Structures code AS3600 (2002). In conclusion, the user guide presents design examples covering typical strengthening scenarios.

The user query based learning system for lifetime prediction of metallic components

Real-World Data Mining Applications generally do not end up with the creation of the models. The use of the model is the final purpose especially in prediction tasks. The problem arises when the model is built based on much more information than that the user can provide in using the model. As a result, the performance of model reduces drastically due to many missing attributes values. This paper develops a new learning system framework, called as User Query Based Learning System (UQBLS), for building data mining models best suitable for users use. We demonstrate its deployment in a real-world application of the lifetime prediction of metallic components in buildings

A user driven data mining process model and learning system

This paper deals with the problem of using the data mining models in a real-world situation where the user can not provide all the inputs with which the predictive model is built. A learning system framework, Query Based Learning System (QBLS), is developed for improving the performance of the predictive models in practice where not all inputs are available for querying to the system. The automatic feature selection algorithm called Query Based Feature Selection (QBFS) is developed for selecting features to obtain a balance between the relative minimum subset of features and the relative maximum classification accuracy. Performance of the QBLS system and the QBFS algorithm is successfully demonstrated with a real-world application

From Prosumer to Produser: Understanding User-Led Content Creation

Alvin Toffler’s image of the prosumer (1970, 1980, 1990) continues to influence in a significant way our understanding of the user-led, collaborative processes of content creation which are today labelled “social media” or “Web 2.0”. A closer look at Toffler’s own description of his prosumer model reveals, however, that it remains firmly grounded in the mass media age: the prosumer is clearly not the self-motivated creative originator and developer of new content which can today be observed in projects ranging from open source software through Wikipedia to Second Life, but simply a particularly well-informed, and therefore both particularly critical and particularly active, consumer. The highly specialised, high end consumers which exist in areas such as hi-fi or car culture are far more representative of the ideal prosumer than the participants in non-commercial (or as yet non-commercial) collaborative projects. And to expect Toffler’s 1970s model of the prosumer to describe these 21st-century phenomena was always an unrealistic expectation, of course. To describe the creative and collaborative participation which today characterises user-led projects such as Wikipedia, terms such as ‘production’ and ‘consumption’ are no longer particularly useful – even in laboured constructions such as ‘commons-based peer-production’ (Benkler 2006) or ‘p2p production’ (Bauwens 2005). In the user communities participating in such forms of content creation, roles as consumers and users have long begun to be inextricably interwoven with those as producer and creator: users are always already also able to be producers of the shared information collection, regardless of whether they are aware of that fact – they have taken on a new, hybrid role which may be best described as that of a produser (Bruns 2008). Projects which build on such produsage can be found in areas from open source software development through citizen journalism to Wikipedia, and beyond this also in multi-user online computer games, filesharing, and even in communities collaborating on the design of material goods. While addressing a range of different challenges, they nonetheless build on a small number of universal key principles. This paper documents these principles and indicates the possible implications of this transition from production and prosumption to produsage.

User behaviours and intentions with digital news media in Australia

This paper summarises findings from a survey of user behaviors and intentions towards digital media and information in Australia. It was undertaken in the first quarter of 2009 by the Queensland University of Technology Creative Industries Faculty and was funded by the Smart Services Cooperative Research Centre. The survey targeted users of 2 news and information sites that are available online only. Findings highlighted differences between the 18-24 year age segment and older users. Social networks (specifically friends and family) were rated as the least reliable, relevant and accurate sources of news. Other findings indicate online news sources that are associated with an established newspaper are highly valued as reliable, relevant and accurate news sources by most people. While most people prefer to use online news sources, there is a great deal of variation in the ways in which people actually use online news. From a total of 524 respondents to the survey it was possible to identify three main types of online news consumers: convenience, loyal and customising users.

The user-led disruption : self-(re)broadcasting at Justin.tv and elsewhere

The rise of videosharing and self-(re)broadcasting Web services is posing new threats to a television industry already struggling with the impact of filesharing networks. This paper outlines these threats, focussing especially on the DIY re-broadcasting of live sports using Websites such as Justin.tv and a range of streaming media networks built on peer-to-peer filesharing technology.

User-Generated Content als Qualitätsmedium? Alternative Anreize für Qualitätscontent

Angetrieben und unterstützt durch Web-2.0-Technologien, gibt es heute einen Trend zur Verbindung der Nutzung und Produktion von Inhalten als Produtzung (engl. produsage ). Um dabei die Qualität der erstellten Inhalte und eine nachhaltige Teilnahme der Nutzer sicherzustellen, müsen vier grundlegende Prinzipien eingehalten werden: * Größtmögliche Offenheit. * Ankurbeln der Gemeinschaft durch Inhalte und Hilfsmittel. * Unterstützung der Gruppendynamik und Abtretung von Verantwortung. * Keine Ausbeutung der Gemeinschaft und ihrer Arbeit.

Attitudes and interests towards biotechnology: The mismatch between students and teachers

Increasing the scientific literacy of Australians has become an educational priority in recent times. The ‘Science State – Smart State’ initiative of the Queensland Government involves an action plan for improving science education that includes a Science for Life action. A desired outcome is for an increased understanding of the natural world so that responsible decisions concerning our future wellbeing can be made in an age of science and technology. Biotechnology is a technology that is having profound impact on our lives. This paper describes how 15-16 year old students and biology teachers revealed a mismatch in both attitudes and interests towards biotechnology between the students and teachers. The findings are of interest as the teachers are writing biotechnology into their work programs in response to new syllabus documents. The teacher’s areas of interest did not match those of the students, possibly resulting in a curriculum the teachers want to teach, but the students do not want to learn.

Collaborative filtering recommender systems using tag information

Recommender Systems is one of the effective tools to deal with information overload issue. Similar with the explicit rating and other implicit rating behaviours such as purchase behaviour, click streams, and browsing history etc., the tagging information implies user’s important personal interests and preferences information, which can be used to recommend personalized items to users. This paper is to explore how to utilize tagging information to do personalized recommendations. Based on the distinctive three dimensional relationships among users, tags and items, a new user profiling and similarity measure method is proposed. The experiments suggest that the proposed approach is better than the traditional collaborative filtering recommender systems using only rating data.

A role mining inspired approach to representing user behaviour in ERP systems

Despite all attempts to prevent fraud, it continues to be a major threat to industry and government. Traditionally, organizations have focused on fraud prevention rather than detection, to combat fraud. In this paper we present a role mining inspired approach to represent user behaviour in Enterprise Resource Planning (ERP) systems, primarily aimed at detecting opportunities to commit fraud or potentially suspicious activities. We have adapted an approach which uses set theory to create transaction profiles based on analysis of user activity records. Based on these transaction profiles, we propose a set of (1) anomaly types to detect potentially suspicious user behaviour and (2) scenarios to identify inadequate segregation of duties in an ERP environment. In addition, we present two algorithms to construct a directed acyclic graph to represent relationships between transaction profiles. Experiments were conducted using a real dataset obtained from a teaching environment and a demonstration dataset, both using SAP R/3, presently the most predominant ERP system. The results of this empirical research demonstrate the effectiveness of the proposed approach.

Beyond the user : use and non-use in HCI

For many, an interest in Human-Computer Interaction is equivalent to an interest in usability. However, using computers is only one way of relating to them, and only one topic from which we can learn about interactions between people and technology. Here, we focus on not using computers – ways not to use them, aspects of not using them, what not using them might mean, and what we might learn by examining non-use as seriously as we examine use.