This study establishes a link between research done in the field of public relations on source credibility, communicator gender, message strength, and source affiliation. Research has established that source credibility is one of the most important factors influencing the acceptance of a message. For this study, source credibility was measured using three main dimensions: expertise, trustworthiness and attractiveness. Similar to many studies focusing on source credibility, this study focuses on the various attributes of the communicator or message source. This study uses an experimental procedure to investigate the relationships between source credibility, message strength, source affiliation, and communicator gender. Based on previous findings, this study hypothesized that higher message strength will be perceived as more credible than lower message strength, sources labeled 'public relations practitioner' will be perceived as less credible than sources that are not, and male communicators will be seen as more credible than females. Findings indicate, however, that message strength has no significant influence on source credibility. Nor does it significantly influence the opinions of the participants on the communicator's gender and their affiliation with the term public relations practitioner, except in the case of their levels of expertise. The results however did indicate that there are statistically significant interactions between the trustworthiness and attractiveness of the source and the attitudes of the participants toward the public relations message, the corporation and their subsequent behavioral intentions.

Cryptography is the art of protecting information by encrypting the original message into an unreadable format. A cryptographic hash function is a hash function which takes an arbitrary length of the text message as input and converts that text into a fixed length of encrypted characters which is infeasible to invert. The values returned by the hash function are called as the message digest or simply hash values. Because of its versatility, hash functions are used in many applications such as message authentication, digital signatures, and password hashing [Thomsen and Knudsen, 2005]. The purpose of this study is to apply Huffman data compression algorithm to the SHA-1 hash function in cryptography. Huffman data compression algorithm is an optimal compression or prefix algorithm where the frequencies of the letters are used to compress the data [Huffman, 1952]. An integrated approach is applied to achieve new compressed hash function by integrating Huffman compressed codes in the core functionality of hashing computation of the original hash function.

Situated within the context of college students’ excessive drinking behaviors, the current study drew from dissonance theory, self-consistency theory, and hypocrisy induction methodology to evaluate the utility of the Communication Theory of Identity within persuasive health message design. Specifically, it examined whether hypocrisy induction manipulations that focused participants on salient identity layers made them mindful of corresponding identity gaps, which in turn caused them to experience cognitive dissonance that they sought to resolve by reporting intentions to change their excessive drinking behavior. Participants (N = 279) completed an online experiment in which they were randomly assigned either to one of four treatment conditions (i.e., traditional hypocrisy, personal-enacted identity gap hypocrisy, relational-enacted identity gap hypocrisy, communal-enacted identity gap hypocrisy) or one control condition. When compared to those in the control condition, participants in the personal-enacted and communal-enacted identity gap hypocrisy conditions reported significantly lower future intentions to engage in excessive drinking. There were no significant differences across conditions, however, in terms of identity gap magnitude or level of cognitive dissonance. These findings are noteworthy, considering that identity gap magnitude was significantly positively related to levels of cognitive dissonance and significantly negatively related to future intentions to engage in excessive drinking. Analyses also explored potential moderating variables in this process, finding that issue involvement moderated the relationship between level of cognitive dissonance and future intentions to engage in excessive drinking, such that intentions were lowest when cognitive dissonance was high and issue involvement was low. Finally, analyses indicated that there was a significant association between experimental condition and level of state reactance, such that participants in the personal-enacted identity gap hypocrisy condition experienced significantly lower levels of state reactance than participants in other conditions. Moreover, there was a significant positive relationship between identity gap magnitude and level of state reactance. The theoretical and contextual implications of these results are discussed. Namely, these results affirm that making message recipients mindful of identity gaps can be a viable persuasive health message design strategy; however, they also suggest that more research is needed to understand how best to make message recipients mindful of identity gaps and how best to integrate identity gaps into persuasive health messages.

Social cohesion among peers profoundly influences decision making during adolescence. Despite this, the current research is very limited concerning the association of social cohesion and intimacy among rural adolescent peers with dietary intake and weight outcomes. This is problematic because social cohesion could be an unknown contributing factor in obesity among rural adolescents. The purpose of this study was to investigate how social cohesion and intimacy among rural adolescents in Kentucky and North Carolina affects the outcomes of a text message intervention aimed at improving fruit, vegetable, fast food and sugar sweetened beverage intake. Additionally, to determine if social cohesion is an independent contributing factor to dietary intakes and weight outcomes among rural adolescents. It was found that the intervention had no effect on fruit and vegetable consumption and purchases and sugar sweetened beverage calories. However, the intervention did have a modest effect on the amount of times fast food was consumed per week.

The current research investigates how and why consumers' construal levels and the appeals framed either by gains or losses jointly influence persuasion. The findings across four experiments indicate that matching high-level construals with gain frames and low-level construals with loss frames leads to a) higher intentions to engage in cholesterol lowering behavior (experiment 1), b) more favorable brand attitudes (experiment 2), c) greater willingness to donate to an environmental organization (experiment 3), and d) higher buying intentions for a brand (experiment 4). It seems that these outcomes occur because matches between construal level and message frames encourage people to pay attention to the information they evaluate (experiments 1 ˜4), and this enhanced attention induces greater perceptions of processing fluency, which in turn leads to positive attitudes (experiments 2˜4). Further, this research demonstrates that an adequate amount of cognitive resources is required for this matching effect to occur (experiment 4). The current research contributes to the construal level, message framing, and matching literatures by unveiling the specific mechanism underlying the matching relationship between construal level and gain versus loss frames on persuasion and by identifying a boundary condition for it. This research also has managerial implications for marketing managers and policymakers in that it suggests a strategic way to use construal level and message frames to enhance marketing communication and advertising effectiveness.

The primary purpose of this study was to examine the potential joint influence of need for cognition (NC), the dispositional preference for engaging in (or avoiding) effortful cognitive processing of information, and type of smoking risk message (i.e., factual and evaluative messages similar in message content and length) on the construction of smoking-relevant risk perceptions among college smokers. A secondary purpose was to examine potential mechanisms through which changes in risk perception might occur. 227 college smokers evaluated one of three pamphlets, (1) a factual (i.e., primarily fact-based) smoking risk pamphlet, (2) an evaluative (i.e., primarily emotion based) smoking risk pamphlet, or (3) a control pamphlet unrelated to smoking. Among occasional smokers, NC interacted with type of risk message to influence perceptions of post-pamphlet risk for several of the risk perception outcomes examined. Specifically, smokers lower in NC reported higher levels of perceived risk in response to the evaluative pamphlet whereas smokers higher in NC reported greater perceived risk in response to the factual pamphlet. The interaction did not predict risk perception outcomes among daily smokers. Significant changes in the mechanisms examined were not observed. Findings provide evidence that NC interacts with type of smoking risk message to influence changes in smoking-related health risk perceptions among occasional college smokers. Theoretical and practical implications are discussed.

Abstract not available

BSD Socket API for Simulator is a project to run untouched Real World Application (RWA) binaries on the powerful modern general-purpose network simulators. BSD Socket API for Simulator is designed to eliminate most of the drawbacks of previous works. It is simulator independence, so it can make use of the powerful functionality and versatile tools provided by modern general-purpose simulators such as NS-2. It is fully compatible with BSD Socket API, so RWA can be run on it without re-linking and re-compiling. It is transparent to the RWA, so RWAs are run on BSD Socket API for Simulator as they are on normal operating systems. BSD Socket API for Simulator is built on the concept of message redirecting. It has two critical parts: shared library and customized simulator application. The shared library is loaded into the address space of RWA. On one hand, messages sent by RWA are captured by the shared library and redirected to the customized simulator application. On the other hand, messages from simulator are redirected by the customized simulator application to the shared library. BSD Socket API for Simulator has been intensively tested. The test results show that it functions as expected and it has an acceptable performance.

Les grappes de calcul sont constituées par l'interconnexion de stations de travail par un réseau plus ou moins performant. Elles rencontrent un large succès dans le domaine du calcul scientifique. De nombreux protocoles et interfaces de programmation ont été développés pour exploiter ces grappes tels que Posix Threads, Marcel, Open MP, Socket, MPI, Madeleine, GM/Myrinet, Corba, etc. Pourtant la programmation d'une application ou le portage d'un environnement de programmation parallèle sur ces grappes est un travail difficile du fait de la complexité et la variété des caractéristiques de ces architectures et des bibliothèques disponibles. L'objectif de cette thèse est de définir et d'évaluer les performances d'INUKTITUT, un interface qui permet de porter efficacement et facilement sur des grappes des applications et des environnements de programmation parallèle de haut niveau comme Athapascan. INUKTITUT contient des fonctions pour multiprogrammation légère et pour les communications à base de message actif : le parallélisme intra-nœuds des processus, est géré à l'aide de processus légers communiquant par la mémoire partagée ; le parallélisme inter-nœuds est exploité par des communications basées sur des messages actifs. INUKTITUT est porté avec succès sur des systèmes aussi différents que Linux, Unix, MacOS X, Windows au dessus de TCP/IP, Myrinet ou Corba. Ce mémoire présente l'architecture d'INUKTITUT et les résultats d'évaluation des performances. Les deux applications principales utilisant INUKTITUT sont : Athapascan, un environnement de programmation parallèle et les KaTools, des outils pour le déploiement efficace de grandes grappes.

Le document présente une synthèse de travaux sur le déploiement, l'utilisation et les techniques de mise en oeuvre d'applications développées selon un modèle de programmation à passage de messages sur des grilles de calcul. La première partie décrit les performances observées sur la période 2002-2006 sur une plateforme à l'échelle de la France, ainsi que les gains obtenus par équilibrage de charge. La deuxième partie décrit un intergiciel nouveau baptisé P2P-MPI qui synthétise un ensemble de propositions pour améliorer la prise en charge de tels programmes à passage de messages.