Clipping noise compensation for OFDMA systems

This paper presents an efficient low-complexity clipping noise compensation scheme for PAR reduced orthogonal frequency division multiple access (OFDMA) systems. Conventional clipping noise compensation schemes proposed for OFDM systems are decision directed schemes which use demodulated data symbols. Thus these schemes fail to deliver expected performance in OFDMA systems where multiple users share a single OFDM symbol and a specific user may only know his/her own modulation scheme. The proposed clipping noise estimation and compensation scheme does not require the knowledge of the demodulated symbols of the other users, making it very promising for OFDMA systems. It uses the equalized output and the reserved tones to reconstruct the signal by compensating the clipping noise. Simulation results show that the proposed scheme can significantly improve the system performance.

Emerging strategies for sponsorship on the Internet

Internet sponsorship is a rapidly evolving communications platform at a fledgling stage for sponsorship-linked marketing. The complex and involving nature of the phenomena offers new research opportunities and the potential for innovative marketing strategies. The Internet presents the opportunity to combine aspects of traditional event/activity sponsorship and media sponsorship innovatively and to extend marketing strategy in new directions. This paper presents an overview of emerging Internet sponsorships strategies, identifies virtual and reality sponsorship opportunities, and explores emerging sponsorship extension strategies that relate to media, brand, channel development, consumer experience, and networking. Finally, future directions for researchers and practitioners are suggested.

Developing a participatory impact assessment approach and action research culture within a communication for social change organisation in Nepal

Developing an effective impact evaluation framework, managing and conducting rigorous impact evaluations, and developing a strong research and evaluation culture within development communication organisations presents many challenges. This is especially so when both the community and organisational context is continually changing and the outcomes of programs are complex and difficult to clearly identify.----- This paper presents a case study from a research project being conducted from 2007-2010 that aims to address these challenges and issues, entitled Assessing Communication for Social Change: A New Agenda in Impact Assessment. Building on previous development communication projects which used ethnographic action research, this project is developing, trailing and rigorously evaluating a participatory impact assessment methodology for assessing the social change impacts of community radio programs in Nepal. This project is a collaboration between Equal Access – Nepal (EAN), Equal Access – International, local stakeholders and listeners, a network of trained community researchers, and a research team from two Australian universities. A key element of the project is the establishment of an organisational culture within EAN that values and supports the impact assessment process being developed, which is based on continuous action learning and improvement. The paper describes the situation related to monitoring and evaluation (M&E) and impact assessment before the project began, in which EAN was often reliant on time-bound studies and ‘success stories’ derived from listener letters and feedback. We then outline the various strategies used in an effort to develop stronger and more effective impact assessment and M&E systems, and the gradual changes that have occurred to date. These changes include a greater understanding of the value of adopting a participatory, holistic, evidence-based approach to impact assessment. We also critically review the many challenges experienced in this process, including:----- • Tension between the pressure from donors to ‘prove’ impacts and the adoption of a bottom-up, participatory approach based on ‘improving’ programs in ways that meet community needs and aspirations.----- • Resistance from the content teams to changing their existing M&E practices and to the perceived complexity of the approach.----- • Lack of meaningful connection between the M&E and content teams.----- • Human resource problems and lack of capacity in analysing qualitative data and reporting results.----- • The contextual challenges, including extreme poverty, wide cultural and linguistic diversity, poor transport and communications infrastructure, and political instability.----- • A general lack of acceptance of the importance of evaluation within Nepal due to accepting everything as fate or ‘natural’ rather than requiring investigation into a problem.

A framework for fully decentralised cycle stealing

Ordinary desktop computers continue to obtain ever more resources – in-creased processing power, memory, network speed and bandwidth – yet these resources spend much of their time underutilised. Cycle stealing frameworks harness these resources so they can be used for high-performance computing. Traditionally cycle stealing systems have used client-server based architectures which place significant limits on their ability to scale and the range of applica-tions they can support. By applying a fully decentralised network model to cycle stealing the limits of centralised models can be overcome. Using decentralised networks in this manner presents some difficulties which have not been encountered in their previous uses. Generally decentralised ap-plications do not require any significant fault tolerance guarantees. High-performance computing on the other hand requires very stringent guarantees to ensure correct results are obtained. Unfortunately mechanisms developed for traditional high-performance computing cannot be simply translated because of their reliance on a reliable storage mechanism. In the highly dynamic world of P2P computing this reliable storage is not available. As part of this research a fault tolerance system has been created which provides considerable reliability without the need for a persistent storage. As well as increased scalability, fully decentralised networks offer the ability for volunteers to communicate directly. This ability provides the possibility of supporting applications whose tasks require direct, message passing style communication. Previous cycle stealing systems have only supported embarrassingly parallel applications and applications with limited forms of communication so a new programming model has been developed which can support this style of communication within a cycle stealing context. In this thesis I present a fully decentralised cycle stealing framework. The framework addresses the problems of providing a reliable fault tolerance sys-tem and supporting direct communication between parallel tasks. The thesis includes a programming model for developing cycle stealing applications with direct inter-process communication and methods for optimising object locality on decentralised networks.

Leveraging sponsorships on the Internet: Activation, congruence, and articulation

This paper considers how the Internet can be used to leverage commercial sponsorships to enhance audience attitudes toward the sponsor. Definitions are offered that distinguish the terms leverage and activation with respect to sponsorship-linked marketing; leveraging encompasses all marketing communications collateral to the sponsorship investment, whereas activation relates to those communications that encourage interaction with the sponsor. Although activation in many instances may be limited to the immediate event-based audience, leveraging sponsorships via sponsors' Web sites enables activation at the mass-media audience level. Results of a Web site navigation experiment demonstrate that activational sponsor Web sites promote more favorable attitudes than do nonactivational Web sites. It is also shown that sponsorsponsee congruence effects generalize to the online environment, and that the effects of sponsorship articulation on audience attitudes are moderated by the commerciality of the explanation for the sponsor-sponsee relationship. Importantly, the study reveals that attitudinal effects associated with variations in leveraging, congruence, and orientation of articulation may be sustained across time.

Consumers' emotional appraisals and action tendencies arising from mobile viral marketing

This study examines consumers' emotional responses to receiving viral mobile marketing communications in comparison to receiving mobile marketing communications where permission has not been given. The study also examines the relationship between these experienced emotions and what action tendencies consumers might consider as a result of these emotions, as well as how they attribute causality for their emotions. Using scenarios in an experimental design, the findings show that there are differences in consumer emotions as a result of the two marketing approaches. The findings also identify relationships between consumers' causal attributions and action tendencies in relation to themselves, the friend sending the viral m-marketing communication and the company involved.

Using the Internet to leverage sponsorships

This study considers the effectiveness of the Internet as a medium through which sponsorship investments can be leveraged. It considers the variables of sponsor-sponsee congruence,articulation, and the extent to which a sponsorship is leveraged via sponsor websites, in relation to consumer attitudes toward brand and company level variables across time. Results show that,consumer attitudes are more favourable for congruent sponsorships, those that are not articulated in commercially-oriented terms, and those that are leveraged via sponsor websites. Additionally, after a seven-day delay, leveraged sponsorships display sustained positive attitudes whereas those not leveraged display a decline in attitudes.

The Figmentum Project: appropriating information and communication technologies to animate our urban fabric

This paper explores how we may design located information and communication technologies (ICTs) to foster community sentiment. It focuses explicitly on possibilities for ICTs to create new modalities of place through exploring key factors such as shared experiences, shared knowledge and shared authorship. To contextualise this discussion in a real world setting, this paper presents FIGMENTUM, a situated generative art application that was developed for and installed in a new urban development. FIGMENTUM is a non-authoritative, non-service based application that aims to trigger emotional and representational place-based communities. Out of this practice-led research comes a theory and a process for designing creative place-based ICT’s to animate our urban communities.

Lesser-known worlds : bridging the telematic flows with located human experience through game design

This paper represents a new theorization of the role of location-based games (LBGs) as potentially playing specific roles in peoples’ access to the culture of cities [22]. A LBG is a game that employs mobile technologies as tools for game play in real world environments. We argue that as a new genre in the field of mobile entertainment, research in this area tends to be preoccupied with the newness of the technology and its commercial possibilities. However, this overlooks its potential to contribute to cultural production. We argue that the potential to contribute to cultural production lies in the capacity of these experiences to enhance relationships between specific groups and new urban spaces. Given that developers can design LBGs to be played with everyday devices in everyday environments, what new creative opportunities are available to everyday people?

MiLK: Transforming everyday places into dynamic learning spaces with mobile and web technologies

This paper explores how game authoring tools can teach processes that transform everyday places into engaging learning spaces. It discusses the motivation inherent in playing games and creating games for others, and how this stimulates an iterative process of creation and reflection and evokes a natural desire to engage in learning. The use of MiLK at the Adelaide Botanic Gardens is offered as a case in point. MiLK is an authoring tool that allows students and teachers to create and share SMS games for mobile phones. A group of South Australian high school students used MiLK to play a game, create their own games and play each other’s games during a day at the gardens. This paper details the learning processes involved in these activities and how the students, without prompting, reflected on their learning, conducted peer assessment, and engaged in a two-way discussion with their teacher about new technologies and their implications for learning. The paper concludes with a discussion of the needs and requirements of 21st century learners and how MiLK can support constructivist and connectivist teaching methods that engage learners and will produce an appropriately skilled future workforce.

Now everything looks like a game : Mobile phones and location-based games.

This paper explores how we may transform peoples’ perceived access to cultural participation by exploiting the possible relationships between place, play and mobile devices. It presents SCOOT; a location-based game in order to investigate how aspects of game-play can be employed to evoke at once playful and culturally meaningful experiences of place. In particular this paper is concerned with how the portable, communicative and social affordances of mobile phones are integral to making a “now everything looks like a game” experience.

Connecting brands with consumers on the internet

There is value of using brands to build relationships with customers and improve brand performance on the web. Products and services are easily replicated; therefore to simplify the buyer decision making process, brands have become important. Building strong brands is important as they can create contrasts between other brands, connections to consumers, and relevance through building customer relationships. Branding in an online environment is important for three reasons: security, recognition and associated costs.

Marketplace forces and the history of retailing : The cycle of control

This paper traces the history of store (retailer-controlled) and national (manufacture controlled)brands; identifies the key historical characteristics of the past 200 years of marketing history;describes the four main time periods of U.S. retail marketing (1800 - 2000); and comments on the most likely developments within the current phases of brand marketing. Will the future focus on technology and new forms of communications? The Internet exemplifies an unconventional retailing environment, with etailer numbers growing rapidly. The central proposition of this paper is that a "cycle of control" - a pattern of marketing developments within the history of retailing and national marketing communications - Can indicate the success of marketing strategies in the future.

Universally composable contributory group key exchange

We treat the security of group key exchange (GKE) in the universal composability (UC) framework. Analyzing GKE protocols in the UC framework naturally addresses attacks by malicious insiders. We define an ideal functionality for GKE that captures contributiveness in addition to other desired security goals. We show that an efficient two-round protocol securely realizes the proposed functionality in the random oracle model. As a result, we obtain the most efficient UC-secure contributory GKE protocol known.

Pedestrians Effects on Indoor MIMO-OFDM Channel Capacity

Temporal variations caused by pedestrian movement can significantly affect the channel capacity of indoor MIMOOFDM wireless systems. This paper compares systematic measurements of MIMO-OFDM channel capacity in presence of pedestrians with predicted MIMO-OFDM channel capacity values using geometric optics-based ray tracing techniques. Capacity results are presented for a single room environment using 5.2 GHz with 2x2, 3x3 and 4x4 arrays as well as a 2.45 GHz narrowband 8x8 MIMO array. The analysis shows an increase of up to 2 b/s/Hz on instant channel capacity with up to 3 pedestrians. There is an increase of up to 1 b/s/Hz in the average capacity of the 4x4 MIMO-OFDM channel when the number of pedestrians goes from 1 to 3. Additionally, an increment of up to 2.5 b/s/Hz in MIMO-OFDM channel capacity was measured for a 4x4 array compared to a 2x2 array in presence of pedestrians. Channel capacity values derived from this analysis are important in terms of understanding the limitations and possibilities for MIMO-OFDM systems in indoor populated environments.