Threshold MACs

The power of sharing computation in a cryptosystem is crucial in several real-life applications of cryptography. Cryptographic primitives and tasks to which threshold cryptosystems have been applied include variants of digital signature, identification, public-key encryption and block ciphers etc. It is desirable to extend the domain of cryptographic primitives which threshold cryptography can be applied to. This paper studies threshold message authentication codes (threshold MACs). Threshold cryptosystems usually use algebraically homomorphic properties of the underlying cryptographic primitives. A typical approach to construct a threshold cryptographic scheme is to combine a (linear) secret sharing scheme with an algebraically homomorphic cryptographic primitive. The lack of algebraic properties of MACs rules out such an approach to share MACs. In this paper, we propose a method of obtaining a threshold MAC using a combinatorial approach. Our method is generic in the sense that it is applicable to any secure conventional MAC by making use of certain combinatorial objects, such as cover-free families and their variants. We discuss the issues of anonymity in threshold cryptography, a subject that has not been addressed previously in the literature in the field, and we show that there are trade-offis between the anonymity and efficiency of threshold MACs.

Shared generation of pseudo-random functions

In Crypto’95, Micali and Sidney proposed a method for shared generation of a pseudo-random function f(·) among n players in such a way that for all the inputs x, any u players can compute f(x) while t or fewer players fail to do so, where 0⩽tsecret seeds S={s1,…,sd} of a poly-random collection of functions, among the n players, each player gets a subset of S, in such a way that any u players together hold all the secret seeds in S while any t or fewer players will lack at least one element from S. The pseudo-random function is then computed as where fsi(·)'s are poly-random functions. One question raised by Micali and Sidney is how to distribute the secret seeds satisfying the above condition such that the number of seeds, d, is as small as possible. In this paper, we continue the work of Micali and Sidney. We first provide a general framework for shared generation of pseudo-random function using cumulative maps. We demonstrate that the Micali–Sidney scheme is a special case of this general construction. We then derive an upper and a lower bound for d. Finally we give a simple, yet efficient, approximation greedy algorithm for generating the secret seeds S in which d is close to the optimum by a factor of at most u ln 2.

Shared generation of pseudo-random functions with cumulative maps

In Crypto’95, Micali and Sidney proposed a method for shared generation of a pseudo-random function f(·) among n players in such a way that for all the inputs x, any u players can compute f(x) while t or fewer players fail to do so, where 0 ≤ t < u ≤ n. The idea behind the Micali-Sidney scheme is to generate and distribute secret seeds S = s1, . . . , sd of a poly-random collection of functions, among the n players, each player gets a subset of S, in such a way that any u players together hold all the secret seeds in S while any t or fewer players will lack at least one element from S. The pseudo-random function is then computed as where f s i (·)’s are poly-random functions. One question raised by Micali and Sidney is how to distribute the secret seeds satisfying the above condition such that the number of seeds, d, is as small as possible. In this paper, we continue the work of Micali and Sidney. We first provide a general framework for shared generation of pseudo-random function using cumulative maps. We demonstrate that the Micali-Sidney scheme is a special case of this general construction.We then derive an upper and a lower bound for d. Finally we give a simple, yet efficient, approximation greedy algorithm for generating the secret seeds S in which d is close to the optimum by a factor of at most u ln 2.

The Habitual Rhythms of Becoming-Involved: Insights into Participation Experiences in Urban Spaces by Children with Diverse Mobility

This chapter reports on a study that reveals the essence of participation in urban spaces by ten children who live with various physical conditions: Muscular Dystrophy, Cerebral Palsy, and Autoimmune Rheumatic Diseases. These conditions affect muscle and movement differently resulting in diverse ways in which children move through space (personal mobility). The children at the time of the research were 9-12 years of age residing in South-east Queensland, Australia. The approach and methods selected for this study, interpretive phenomenological inquiry and grounded theory, were chosen for their capacity to capture the complexity and multiple interactions of the child’s urban living. The confronting and poignant accounts by children and their families of their experiences produced a new way of understanding the concept of participation, as a ‘journey of becoming involved.’ Their accounts of performing everyday routines (e.g. leaving home, getting in and out of the car, and entering places) in urban spaces (neighbourhood streets, schools, open spaces, shopping centres, and hospitals) revealed differences in the way settings were experienced. These differences were associated with the interplay between the body, space and context. Where interplays were problematic, explicit decisions about children’s involvement were made. These decisions were described in terms of ‘avoid going’, ‘pick and choose’, ‘discontinue’, ‘accept’, or ‘contest.’ What these decisions mean is some spaces are avoided, some journeys are discontinued, and some barriers encountered in journeys are normalised as everyday experiences, i.e. ‘tolerable discrimination’. These actions resulted in experiences of non-participation or partial–tokenistic participation. The key substantive contribution of the research lies in the identification of points in children’s journeys that shape participation experience. These points identify where future interventions in policy, programming and design can be made to make real and sustaining changes to lives of children and their families in geographies crucial to urban living.

The effectiveness of workshops as managerial learning opportunities

Purpose The purpose of this paper is to examine the effectiveness of workshops as a learning tool for small business owner‐managers (SBO‐Ms). It aims to concentrate on workshops delivered over 18 months from January 2007 to July 2008 as part of several publicly‐funded small business development programmes in two Australian local government areas (LGAs). Design/methodology/approach Effectiveness is measured in terms of meeting the overarching learning needs and expectations of participants in the context of the programme goals. The paper analyses data gathered from workshop participants either post‐workshop, in later focus groups or through a questionnaire as well as additional feedback from participants and the organisers' reflections. The thematic analysis is organised through an analogy of “going shopping”, where the SBO‐M shopper is buying “learning” when they attend a workshop. Findings Understanding motivation to participate or the “what's in it for me” is important as SBO‐Ms tend to be reluctant, resist or fail to engage with externally sponsored business support initiatives. Workshops were valued for the “space” they create to reflect on practice. For many SBO‐Ms, content “comes alive” with discussion while networking helps reduce the isolation SBO‐Ms can feel. Practical implications The shopping analogy suggests workshops must cater for purposeful shoppers as well as browsers, while interaction with others in the workshop is critical to realising the value of workshops. Originality/value Knowing whether, and how, workshops deliver learning can help to better target and refine these types of support initiatives to ensure they provide positive outcomes for individuals, organisations and economies.

Engaging children and young people in creating resilient and healthy urban spaces

Urban public space in Australia and internationally, can be critically examined from a number of multidisciplinary standpoints, including human geography, urban design, planning, sociology, and public health. Viewing urban public space from a range of perspectives encourages different vantage points to emerge and questions around health, wellbeing and public space are increasingly topical and important in the broadest of terms, with public space being a key arena for physical activity, mental health, commercial, cultural and community life and the possibility of social inclusion. However, in the name of urban regeneration, programs of securitisation, ‘gentrification’ ‘creative’ and ‘smart’ city initiatives refashion public space as sites of selective inclusion and exclusion (Watson 2005; Gabrys 2014). In this context of monitoring and control procedures, in particular, children and young people’s use of space in parks, neighbourhoods, shopping malls and streets, is often viewed as a threat to social order, requiring various forms of remedial action, such as being ‘designed out’ of public space (Johnson 2014). Rarely are children and young people actively and respectfully brought into planning and governance processes and consequently many urban public spaces are essentially adult places, where control and ongoing surveillance are the key concerns (Freeman 2011, Dee 2013). There is also a political economy of public space discernable in cities like Brisbane, where ‘flagship’ infrastructure such as road tunnels take pride of place, while more humbly appointed pedestrian footpaths are often narrow, in a poor state of repair and a potential barrier to good health (Atkinson and Easthope 2009). The recent development of bikeways in Brisbane is a case in point, presenting both challenges and opportunities in being a valuable new form of public space heavily used by ‘commuter cyclists’ by day, but poorly lit and conceived, for a range of users at other times (Wyeth 2014). This paper concentrates on questions of social citizenship rights and discourses of health and wellbeing and suggests that cities, places and spaces and those who seek to use them, can be resilient in maintaining and extending democratic freedoms, calling surveillance, planning and governance systems to account (Smith 2014). The active inclusion of children and young people better informs the implementation of public policy around the design, build and governance of public space and also understandings of urban citizenship, leading to healthier, more inclusive, public space for all (Jacobs 1965).

Young people and the struggle for public space in Australia

Public Space is important to the overall health and wellbeing of children and young people in allowing them to explore their local and wider community, meet up with friends, get some exercise and feel included in the society in which they live. A problem exists in the capacity of modern, urban public space to genuinely accommodate children and young people’s need to experience excitement and fun in what has been termed “unprogrammed space” (Lynch 1977:71), or simply to ‘hang out’ in unstructured social space, with control by civic authorities a key concern. For many children and young people, their experiences of attempting to use public space are sometimes marred by the denial of everyday rights and courtesies, in youth ‘unfriendly’ spaces and this is often the case in shopping centres in Australia as expolored in this paper.

Public space and the marginalisation of children and young people

Throughout Australia (and elsewhere in the world) public spaces are under attack by developers and also attempts by civic authorities to regulate, restrict and reframe them. A consequence of the increasingly security driven, privatised and surveilled nature of public space is the exclusion and displacement of those considered flawed and unwelcome in the “spectacular” consumption spaces of major urban centres. In this context of monitoring and control procedures, children and young people’s use of public space in parks, neighbourhoods, shopping malls and streets is often viewed as a threat to social order, requiring various forms of punitive and/or remedial action. This paper discusses developments in the surveillance, governance and control of public space used by children and young people in particular and the capacity for their displacement and marginality, diminishing their sense of belonging, wellbeing and right to public space as an expression of social, political and civil citizenship.

The hunt

"Information Thru Play: In 2010, responding to the success of The Threshold, Juxt Interactive again asked No Mimes Media, to partner in creating a transmedia experience to entertain and inform Cisco's Global Sales Force. The Hunt put employees at the center of a thriller where characters sent and responded to their emails, left phone messages, communicated through Facebook and Twitter, even asked them to retrieve items from a dead drop and to send them photographs and information. And while helping fictional characters Isabel and Keith escape an ancient secret organization, the sales force also learned about new Cisco technologies coming to market. Cisco had new demands for the 2010 experience. A geographically and culturally dispersed sales force raises challenges when it comes to introducing dozens of new products and technologies each year. Cisco wanted The Hunt to have global reach, to educate, to build collaboration, and to be fun. This demanded new ways of storytelling and new ways of thinking. The Hunt was quick and intense, unfolding in real time in just two weeks. Many experienced players were poised to participate and expectations were high. Many of the mechanics of the previous year's experience were repeated, and the audience ripped through the opening, discovering video clips and websites in minutes. The surprise was discovering Facebook and Twitter accounts, where characters responded to player postings and comments in real time. The Hunt involved audience members from countries around the world, including China, India, Netherlands, Germany, Norway, Pakistan, Japan, the United Kingdom, and the United States. It highlighted new Cisco technologies like Pulse and Mediator, painlessly engaging the audience in what those technologies do and how they work. Players collaborated across silos, creating networks of cross-disciplinary experts. The Hunt pushed the boundaries of storytelling, with events unfolding on Twitter and Facebook, and in the real world where the audience had to use social engineering to find and secure a package with vital information. With thousands of players highly engaged around the world, The Hunt once again proved that transmedia experiences can effectively be used to not only meet the goals of a brand, but entertain their audience as well."

Conspiracy for good

"Tim Kring, Creator of the hit television show 'Heroes' tells how the big idea began, and where you can jump in. "A few years ago, I started thinking about an entirely new way to tell a story, far different from traditional TV. I didn't just want to talk about 'saving the world' in fiction, I wanted to create a narrative that spilled out into the streets. One that you could live inside of for a while. How cool would it be, I thought, to create a story that exists all around you all of the time? On your laptop, your mobile phone, on your sidewalks, as a secret message hidden in your favorite song or while standing at the bus stop on your way to work. And, taking it further, what if your participation over a few weeks or months actually impacts the story's development and creates positive change in the real world because a philanthropic mission is integrated into the narrative itself? The Conspiracy For Good is the culmination of this dream. This is the pilot project for a first-of-itskind interactive story that empowers its audience to take real-life action and create positive change in the world. Call it Social Benefit Storytelling. To achieve this, I need you to participate. Reality and fiction have to blur. Every story needs a villain and you will meet the villain in the STORY SO FAR section on this site. And every story needs a hero. That's where YOU come in. As part of The Conspiracy For Good you will join a collective of thinkers, artists, musicians, and causes, creating a unified voice to fight the forces of social and environmental injustice. This is our site, where together we can follow the story and build a community that focuses on changing the world for the better, one person and one action at a time. Welcome to the Conspiracy." Tim Kring"

Form-based planning and liveable urban environments

This review article discusses form-based planning an din details analise the following books: Stepehn Marshall (2012) Urban Coding and Planning (Routledge, New York, USA, 272pp. pISBN 1135689202). Emily Talen (2012) City Rules: How Regulations Affects Urban Form (Island Press, Washington DC, USA, 254 pp. ISBN 9781597266925). Richard Tomlinson (2012) Australia’s Unintended Cities: the Impact of Housing on Urban Development (CSIRO Publishing, Collingwood, Australia, 194pp. ISBN 9780643103771). The history of the city has been written and rewritten many times: the seminal works of Benevolo (1980) and Mumford (1989) reconstruct how settlements, particularly their urban form, have changed over centuries. Rowe and Koetter (1978), Kostof (1991, 1992), Krier (2003), and Rossi and Eisenmann (1982) address instead the components that shape the urban environment: the architect can aggregate and manipulate squares, streets, parks and public buildings to control urban design. Generally these studies aim to reveal the secret of the traditional city in contraposition to the contemporary townscape characterized by planning and zoning, which are generally regarded as problematic and sterile (Woodward, 2013). The ‘secret rules’ that have shaped our cities have a bearing on the relationship of spaces, mixed uses, public environments and walkability (Walters, 2011)...

Online Customer Experience : What is the Experience and how is it Difference for Frequent and Infrequent Purchasers, Age Cohorts and Gender Groups?

What do we know? • Customer Experience is increasingly becoming the new standard for differentiation in both offline and online retailing, and offers a sustainable competitive advantage. o The economic value of a company’s offering has been observed to increase when the customer has a fulfilling shopping experience (Pine & Gilmore, 1998) o Crafting engaging and customer experience is a known method of generating loyalty, advocacy and word of mouth (Tynan & McKechnie, 2009). o A good experience can entice consumers to shop for longer and spend more (Kim, 2001). • The customer’s experience is made up of diverse elements occurring before, during and after the purchase itself. (Discussed further on page 5). It is cumulative over time and can be influenced by touch points across multiple channels. What remains unclear? • How do Coles customers respond to the elements of online customer experience? • How does the online customer experience differ for frequent and infrequent purchasers? • Do differences between genders and age cohorts for online customer experience exist?

Understanding public response to a congestion charge : a random-effects ordered logit approach

Public acceptance is consistently listed as having an enormous impact on the implementation and success of a congestion charge scheme. This paper investigates public acceptance of such a scheme in Australia. Surveys were conducted in Brisbane and Melbourne, the two fastest growing Australian cities. Using an ordered logit modeling approach, the survey data including stated preferences were analyzed to pinpoint the important factors influencing people’s attitudes to a congestion charge and, in turn, to their transport mode choices. To accommodate the nature of, and to account for the resulting heterogeneity of the panel data, random effects were considered in the models. As expected, this study found that the amount of the congestion charge and the financial benefits of implementing it have a significant influence on respondents’ support for the charge and on the likelihood of their taking a bus to city areas. However, respondents’ current primary transport mode for travelling to the city areas has a more pronounced impact. Meanwhile, respondents’ perceptions of the congestion charge’s role in protecting the environment by reducing vehicle emissions, and of the extent to which the charge would mean that they travelled less frequently to the city for shopping or entertainment, also have a significant impact on their level of support for its implementation. We also found and explained notable differences across two cities. Finally, findings from this study have been fully discussed in relation to the literature.

Amazing tale of teen's survival in torrent gives hope to families of the missing

Flailing in a maelstrom of muddy water, a teenager being swept along Toowoomba's shopping strip has become a reason for hope for the loved ones of the 12 people still missing in the devastating Queensland floods...

Telecommunications Impacts on the Structure and Organisation of Male Sex Work

(Sub)Urban Sexscapes brings together a collection of theoretically-informed and empirically rich case studies highlighting the contemporary and historical geographies and regulation of the commercial sex industry. Contributions in this edited volume examine the spatial and regulatory contours of the sex industry from a range of disciplinary perspectives—urban planning, urban geography, urban sociology, and, cultural and media studies—and geographical contexts—Australia, the UK, US and North Africa. In overall terms, (Sub)urban Sexscapes highlights the mainstreaming of commercial sex premises—sex shops, brothels, strip clubs and queer spaces—and products—sex toys, erotic literature and pornography—now being commonplace in night time economy spaces, the high street, suburban shopping centres and the home. In addition, the aesthetics of commercial and alternative sexual practices—BDSM and pornography—permeate the (sub)urban landscape via billboards, newspapers and magazines, television, music videos and the Internet. The role of sex, sexuality and commercialized sex, in contributing to the general character of our cities cannot be ignored. In short, there is a need for policy-makers to be realistic about the historical, contemporary and future presence of the sex industry. Ultimately, the regulation of the sex industry should be informed by evidence as opposed to moral panics.