We present a distributed data structure, which we call "RootChord". To our knowledge, this is the first distributed hash table which is able to adapt to changes in the size of the network and answer lookup queries within a guaranteed two hops while maintaining a routing table of size Theta(sqrt(N)). We provide pseudocode and analysis for all aspects of the protocol including routing, joining, maintaining, and departing the network. In addition we discuss the practical implementation issues of parallelization, data replication, remote procedure calls, dead node discovery, and network convergence.

The requirements of modern e-learning techniques change. Aspects such as community interaction, flexibility, pervasive learning and increasing mobility in communication habits become more important. To meet these challenges e-learning platforms must provide support on mobile learning. Most approaches try to adopt centralised and static e-learning mechanisms to mobile devices. However, often technically it is not possible for all kinds of devices to be connected to a central server. Therefore we introduce an application of a mobile e-learning network which operates totally decentralised with the help of an underlying ad hoc network architecture. Furthermore the concept of ad hoc messaging network (AMNET) is used as basis system architecture for our approach to implement a platform for pervasive mobile e-learning.

Les charges réelles d'applications sont souvent dynamiques. Ainsi, le dimensionnement statique de ressources est voué soit au gaspillage, s'il est basé sur une estimation du pire scénario, soit à la dégradation de performance, s'il est basé sur la charge moyenne. Grâce au modèle du cloud computing, les ressources peuvent être allouées à la demande et le dimensionnement adapté à la variation de la charge. Cependant, après avoir exploré les travaux existants, nous avons trouvé que la plupart des outils d'élasticité sont trop génériques et ne parviennent pas à répondre aux besoins spécifiques d'applications particulières. Dans le cadre de ce travail, nous utilisons des boucles autonomiques et diverses techniques d'élasticité afin de rendre élastiques différents types d'applications, à savoir un service de consolidation, un intergiciel de messagerie et une plateforme de traitement de données en temps-réel. Ces solutions élastiques ont été réalisées à partir d'applications libres et leur évaluation montre qu'ils permettent d'économiser les ressources utilisées avec un surcoût minimal. / Real world workloads are often dynamic. This makes the static scaling of resourcesfatally result in either the waste of resources, if it is based on the estimatedworst case scenario, or the degradation of performance if it is based on the averageworkload. Thanks to the cloud computing model, resources can be provisioned ondemand and scaling can be adapted to the variations of the workload thus achievingelasticity. However, after exploring the existing works, we find that most elasticityframeworks are too generic and fail to meet the specific needs of particularapplications. In this work, we use autonomic loops along with various elasticitytechniques in order to render different types of applications elastic, namelya consolidation service, message-oriented middleware and a stream processingplatform. These elastic solutions have been implemented based on open-sourceapplications and their evaluation shows that they enable resources’ economy withminimal overhead.

People connect digitally through social media, fusing their relationships with meaning in a non-space of relational potential--a translucent and fluctuating enclave where the self becomes elastic. This thesis explores how I have formed bonds in virtual space through ritual interaction. Looking at the ways I learned to use technology through the progression of a close personal relationship, I suggest that social media use is a performance of identity--a virtuality that exposes how people negotiate the digital enclosure of contemporary society. My story is one of digital nativity and reclaiming love through virtual performance. I show how these performances have had a profound impact on my understanding of self-in-relation-to-other. Finally, I put forth a theory of Real Virtuality, suggesting that virtual reality has escaped the confines of the machine. Thus, digital conversations penetrate offline social situations in ways that have stirring consequences for people in the digital age.

<p>Text communication is often perceived as lacking some components of communication that are essential in sustaining interaction or conversation. This interaction incoherency tends to make&nbsp / text communication plastic. It is traditionally devoid of intonation, pitch, gesture, facial expression and visual or auditory cues. Nevertheless, Instant Messaging (IM), a form of text communication is on the upward uptake both on PCs and on mobile handhelds. There is a need to rubberise this plastic text messaging to improve co-presence for text communications thereby improving&nbsp / synchronous textual discussion, especially on handheld devices. One element of interaction is gesture, seen as a natural way of conversing. Attaining some level of interaction naturalism&nbsp / requires improving synchronous communication spontaneity, partly achieved by enhancing input mechanisms. To enhance input mechanisms for interactive text-based chat on mobile devices,&nbsp / there is a need to facilitate gesture input. Enhancement is achievable in a number of ways, such as input mechanism redesigning and input offering adaptation. This thesis explores affective gesture mode on interface redesign as an input offering adaptation. This is done without a major physical reconstruction of handheld devices. This thesis presents a text only IM system built on&nbsp / Session Initiation Protocol (SIP) and SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE). It was developed with a novel user-defined hotkey implemented as a one-click context menu to &ldquo / fast-track&rdquo / text-gestures and emoticons. A hybrid quantitative and qualitative approach was taken to enable data triangulation. Results from experimental trials show that an&nbsp / Affective Gesture (AG)approach improved IM chat spontaneity/response. Feedback from the user trials affirms that AG hotkey improves chat responsiveness, thus enhancing chat spontaneity.</p>

Increased globalization and the thought of converging values has lead marketing practitioners and academics to consider more standardized approaches to marketing and advertising strategies. Even though cultures seem to evolve closer to each other, cultural diversity still exists. Advertising reflects and influences our cultural values and therefore it cannot be ignored when building effective advertising. Results show that culture impacts execution more than creative strategy (Wei &amp; Jiang, 2005) and therefor execution is seen as an important element of cross-cultural marketing and advertising. The emergence of new social media channels is raising the question whether previous execution styles are suitable for these marketing channels and whether similar connection with the culture exists. This thesis examines how cultural characteristics are reflected in advertising execution and draws special attention to the marketing communication through mobile messaging applications. However, this study takes new approach for viewing culture’s influence on advertising executions by exploring the preferences of audience. This research aims to shed light on the under researched area of cross-cultural advertising in Asian region in terms of two culturally similar countries. This study examines Chinese and South Korean preferences and perceptions of execution styles and explores to what extent similarities and differences occur. These similarities and differences are analyzed in terms of culture and whether these findings can be attributed to the nations' cultural characteristics. To address the topic holistically in its cultural context, a qualitative mixed-methods research approach was adopted for this research. This present study combines cultural and advertising theories to produce a theoretical frame for data collection and further analysis. Findings indicate that culture does influence execution preferences even in rather similar cultures. Although advertising reflects nations’ cultural values, it does not directly translate into the preferences of that audience. This study indicated that the channel of marketing communication influences execution preferences. Mobile messaging application as a marketing channel was seen affecting the preferences of Chinese and Koreans towards more direct and informational communication which have been considered untypical for East Asian cultures. However, overall changes in the preferences appeared indicating value shift, changes in the expressions of culture, or paradoxal values. Results suggest that cross-cultural marketers and advertisers should recognize the importance of cultural characteristics when planning and designing execution strategies.

Recent developments in embedded systems give robots access to the Internet and make them more flexible and capable of performing more complex applications. However, these robots are still limited in terms of size, CPU power, storage resources and memory. Consequently, these robots have only been manufactured for certain specific applications and cannot be re-used for other applications. This presents us with a challenge to design a software framework - Robot Colony. The Robot Colony enables robots to be suitable for a wide range of applications, not originally received from manufacturers, to achieve greater functionality, flexibility and utility. This research outlines the architecture and functionality of the Robot Colony to support the collaboration between devices in the P2P community and also analyse the JXTA platform, which was the framework originally proposed. Lastly we present a customized P2P architecture that specifically addresses the interaction betweensoftware components across the network. We further discuss the following technologies applied in theframework: * XML-based Directory Service Provider * HTTP-based publish/describe control commands * Remote Process Invoke To fully complete the project, a thorough evaluation of the framework based on either the JXTAplatform or the customized P2P channel has been conducted. This evaluation provides basic statistics data for the proposed framework design and implementation. Further more, we have presented a realtime Demo at the Smart Device lab of the Queensland University of Technology.

This research set out to determine factors associated with text bullying. It examined the relationship between personality traits and the level of hostility expressed by students in reaction to sample text messages. One hundred and ninety eight girls aged 13 and 14 in Canada and New Zealand volunteered to complete a questionnaire consisting of four personality measures - the impulsivity subscale of the PRF-E, cynical distrust scale (revised), needs for power scale (revised), and the rejection sensitivity scale (adult, short). The survey also rated their proposed likely response to eight sample text messages that covered four themes and to two levels of intensity. Results using Pearson’s r correlation of .01 demonstrated a significant relationship between hostility and impulsivity. There was no significant difference in either the results of the personality measures or their level of hostility between the results of the Canadian and New Zealand participants. How these findings contribute to the current theoretical knowledge of adolescent bullying and the practical application of these findings for schools are also discussed.

Les charges réelles d'applications sont souvent dynamiques. Ainsi, le dimensionnement statique de ressources est voué soit au gaspillage, s'il est basé sur une estimation du pire scénario, soit à la dégradation de performance, s'il est basé sur la charge moyenne. Grâce au modèle du cloud computing, les ressources peuvent être allouées à la demande et le dimensionnement adapté à la variation de la charge. Cependant, après avoir exploré les travaux existants, nous avons trouvé que la plupart des outils d'élasticité sont trop génériques et ne parviennent pas à répondre aux besoins spécifiques d'applications particulières. Dans le cadre de ce travail, nous utilisons des boucles autonomiques et diverses techniques d'élasticité afin de rendre élastiques différents types d'applications, à savoir un service de consolidation, un intergiciel de messagerie et une plateforme de traitement de données en temps-réel. Ces solutions élastiques ont été réalisées à partir d'applications libres et leur évaluation montre qu'ils permettent d'économiser les ressources utilisées avec un surcoût minimal. / Real world workloads are often dynamic. This makes the static scaling of resourcesfatally result in either the waste of resources, if it is based on the estimatedworst case scenario, or the degradation of performance if it is based on the averageworkload. Thanks to the cloud computing model, resources can be provisioned ondemand and scaling can be adapted to the variations of the workload thus achievingelasticity. However, after exploring the existing works, we find that most elasticityframeworks are too generic and fail to meet the specific needs of particularapplications. In this work, we use autonomic loops along with various elasticitytechniques in order to render different types of applications elastic, namelya consolidation service, message-oriented middleware and a stream processingplatform. These elastic solutions have been implemented based on open-sourceapplications and their evaluation shows that they enable resources’ economy withminimal overhead.

Submitted by (lucia.rodrigues@ufrpe.br) on 2016-09-21T12:48:54Z No. of bitstreams: 1 Diogo Francisco Borba Rodrigues.pdf: 1924185 bytes, checksum: 9fc99c1e969769f5429de4703c66669d (MD5) / Made available in DSpace on 2016-09-21T12:48:54Z (GMT). No. of bitstreams: 1 Diogo Francisco Borba Rodrigues.pdf: 1924185 bytes, checksum: 9fc99c1e969769f5429de4703c66669d (MD5) Previous issue date: 2013-02-21 / Models and software have been developed for irrigation management, however they don’t reach small farmers due to technical and economic limitations. This study aimed to develop tools for irrigation management using mobile phone, a technology already assimilated by society. The first tool called IGmanejo sends SMS to farmers with area’s name, irrigation depth and run time. The second tool is a Java application for mobile phone (mobile IGmanejo), which support irrigation management to farmers who have irrigation evaporimeter tank and rain gauge. This paper intend support a public policy of rational use of water in the semiarid region of Brazil, since it is free to farmer and may solve the current gap in irrigation technical assistance. Training curse to be able software use, climate monitoring equipment and sensitization of farmers to adopt such technology are essential points to success on farm. This software was evaluated according to water saving to growing cabbage crop, under three different seasons. The management simulations were done on a small farm, in Pernambuco state. Irrigation depth send by SMS IGmanejo water saving in 20% compared to reference software CropWat (FAO). For mobile IGmanejo were done two simulations of irrigation, using data from gauge evaporimeter tank (Class A) and using simplified tank, and also compared with those obtained by IGmanejo SMS. The results did not present statistically significant differences, confirming that the farmer may use more economical methods to estimate evapotranspiration (like simplified tank) instead of class A tank, which has high cost. The software showed that it is able to reduce of use of water on agriculture going to remote regions to support irrigation management with simplicity and quality. / Diversos modelos e software têm sido desenvolvidos para o manejo de irrigação, no entanto eles não conseguem atingir pequenos agricultores devido a limitações técnicas e econômicas. O presente trabalho teve por objetivo desenvolver ferramentas de manejo de irrigação utilizando telefone celular, uma tecnologia já assimilada pela sociedade. A primeira ferramenta chamada de IGmanejo que envia SMS com o nome da área, a lâmina e o tempo de irrigação para agricultores previamente cadastrados. A segunda ferramenta é um aplicativo Java para telefone celular (IGmanejo mobile), que orienta o manejo de irrigação para agricultores que possuam tanque evaporimétrico e pluviômetro. Este trabalho pretende auxiliar na definição de uma política pública do uso racional de água no semiárido do Brasil, uma vez que não terá custo para o agricultor e, poderá auxiliar a lacuna existente hoje na assistência técnica especializada em irrigação no nordeste. Cursos de capacitação para uso do software, dos equipamentos de monitoramento climático e de sensibilização dos agricultores em adotar tal tecnologia são essenciais para a chegada com êxito dessa ferramenta no campo. Os softwares propostos neste trabalho foram validados de acordo com a economia de água obtida durante o ciclo da cultura do repolho, onde o início do cultivo foi simulado em três diferentes épocas do ano. As simulações de manejo foram realizadas em uma área de agricultura familiar situada no município de Pesqueira-PE. A lâmina de irrigação do IGmanejo SMS obteve 20% de economia de água quando comparada com a lâmina obtida pelo software de referência CropWat da FAO. Para o aplicativo IGmanejo mobile foram realizadas duas simulações de lâminas de irrigação, uma utilizando dados de tanque classe A e outra utilizando dados do tanque alternativo (classe B), e ainda foram comparadas com as lâminas obtidas do IGmanejo SMS. Os resultados não diferiram estatisticamente entre si, ratificando o fato de que o agricultor pode recorrer a métodos mais econômicos para estimativa da evapotranspiração com auxílio de tanques alternativos ao invés do tanque classe A, que possui custo elevado. Os softwares propostos mostraram que são capazes de reduzir o desperdício de água na agricultura e levar até áreas remotas a orientação para um manejo de irrigação com simplicidade e qualidade.