Th.--Philos.--Paris 1, 1988. / Bibliogr. p. 491.

Magister Scientiae - MSc / A semi-synchronous environment consists of a combination of synchronous and asynchronous transport media used to transport messages from source to destination. This thesis explores an empirical solution for guaranteeing the delivery of messages in a multimodal semi-synchronous environment for a Deaf Telephony application. SoftBridge for Instant Messaging Bridging Application (SIMBA), is a communication platform that make use of a semi-synchronous framework to allow a hearing and Deaf person to communicate inside a single uniform space. SIMBA was modified to provide reliability for both synchronous and asynchronous transport media. In the process of modification, SIMBA was renamed to NaradaBrokering integrated in SIMBA (NIMBA). Within the literature various systems are analyzed and successes and failures are distilled to help formulate a good solution for the thesis question. To guarantee asynchronous messages sent, the Message Oriented Middleware (MOM) paradigm was used with Forward Error Correction (FEC) used to guarantee the delivery of synchronous messages sent. The work forms part of a social study conducted at the Deaf Community of Cape Town (DCCT) community centre. Ethnography was used to identify the requirements for a Deaf Telephony application. Thus, this thesis is based on a socio- technical environment where the system is developed in a laboratory and tested in an actual community. Results show that these solutions are cceptable for a semi-synchronous communication environment. However, interviews conducted with a select group of Deaf participants showed that cell phones are currently too popular to be replaced by NIMBA as a primary communication device and service. This is due to the immense popularity of Short Message Service (SMS) among the Deaf and cell phone devices mobile capabilities. The overall goal of the thesis is to guarantee delivery for a semisynchronous environment with broader implications of showing how multimodal semi-synchronous services like Deaf Telephony can be made attractive to service providers concerned with reliability in the new Internet Protocol (IP) world of telecommunications. / South Africa

Master of Agribusiness / Department of Agricultural Economics / Vincent R. Amanor-Boadu / There is an opportunity to develop an instant noodle manufacturing plant in Argentina to manufacture and market branded and private-label instant noodles. This opportunity has arisen from a number of factors. First, the increasing time compression that confronts consumers has created an emergence of consumers who are looking for quick meals that are also healthy. Second, the growing incomes that are being experienced across all income classes have created a demand for processed food products across all consumer markets. Third, potential competitors are not seeing the market trends and, thus, create an opportunity to gain a first mover advantage in this burgeoning market. Finally, the policies that are being developed by the government have created an import-replacement mentality that presents significant opportunities to build specific strategic alliances to seize an opportunity such as this one. This thesis presents the feasibility of seizing this opportunity to build a manufacturing facility to produce and market instant noodles in Argentina. It assesses the technical and economic dimensions of the feasibility process and presents financial analyses of the potential outcome for investors. The researcher is leading the project and participating in the investment process. Therefore, the outcome of this thesis has direct implications for the wellbeing of the researcher beyond partial fulfillment of degree requirements. The results show that the opportunity is credible and profitable over a 20-year period. The Net Present Value of the investment is positive and its Internal Rate of Return of 26 percent is higher than the company’s hurdle rate of 15 percent. To this end, it suggested that the investment must go ahead. However, the sensitivity analysis shows that at the initial production level of 60,000 packets per shift, the project is very sensitive to the number of shifts that are run per day. Indeed, if the company runs one shift for the first three years instead of the first two years and two shifts for the next three years instead of Years 3 and 4, the project is not economically feasible. On the other hand, building a larger plant, one that produces 120,000 packets per shift, protects the plant from this vulnerability. The internal rate of return is 40 percent and the NPV is in excess of $5 million over 20 years. Therefore, the recommendation is to build the larget plant and enhance the robustness of the plant.

Instant Messaging (IM) has grown tremendously over the last few years. Even though IM was originally developed as a social chat system, it has found a place in many companies, where it is being used as an essential business tool. However, many businesses rely on free IM and have not implemented a secure corporate IM solution. Most free IM clients were never intended for use in the workplace and, therefore, lack strong security features and administrative control. Consequently, free IM clients can provide attackers with an entry point for malicious code in an organization’s network that can ultimately lead to a company’s information assets being compromised. Therefore, even though free IM allows for better collaboration in the workplace, it comes at a cost, as the title of this dissertation suggests. This dissertation sets out to answer the question of how free IM can facilitate an attack on a company’s information assets. To answer the research question, the dissertation defines an IM attack model that models the ways in which an information system can be attacked when free IM is used within an organization. The IM attack model was created by categorising IM threats using the STRIDE threat classification scheme. The attacks that realize the categorised threats were then modelled using attack trees as the chosen attack modelling tool. Attack trees were chosen because of their ability to model the sequence of attacker actions during an attack. The author defined an enhanced graphical notation that was adopted for the attack trees used to create the IM attack model. The enhanced attack tree notation extends traditional attack trees to allow nodes in the trees to be of different classes and, therefore, allows attack trees to convey more information. During the process of defining the IM attack model, a number of experiments were conducted where IM vulnerabilities were exploited. Thereafter, a case study was constructed to document a simulated attack on an information system that involves the exploitation of IM vulnerabilities. The case study demonstrates how an attacker’s attack path relates to the IM attack model in a practical scenario. The IM attack model provides insight into how IM can facilitate an attack on a company’s information assets. The creation of the attack model for free IM lead to several realizations. The IM attack model revealed that even though the use of free IM clients may seem harmless, such IM clients can facilitate an attack on a company’s information assets. Furthermore, certain IM vulnerabilities may not pose a great risk by themselves, but when combined with the exploitation of other vulnerabilities, a much greater threat can be realized. These realizations hold true to what French playwright Jean Anouilh once said: “What you get free costs too much”.

Instant messaging applications noted significant grow especially in the last decade. In fact, the Internet communication is cheap and convenient way how to communicate with distant people. However, this grow of user communication and data exchange through the online world impacts user security and privacy, as it was also shown recently by WhatsApp privacy issues. Firstly this article evaluates security and privacy issues of current mobile messaging applications. Secondly, we design our basic open source solution with the focus on security, privacy, and user centric features. Furthermore, we provide proof-of-concept implementation of our system

Group chat facilitates remote collaboration and idea exchanges. With the widespread use of group chat for productive information exchanges, it becomes dicult for members of groups to keep up and stay grounded during the long stream of conversation that is generated. I conducted a need-finding study where I simulated group chat conversations in the context of collaboration to learn about issues and behaviors in a group chat when the size of the group chat is 5 or 10. The study participants also filled out a survey post the group chat, describing their challenges and issues with the group chat. A grounded theory approach analyses of the data collected, and the chat conversation gave us several themes. Our results show that participants generally felt that there were too many messages. A majority of the participants found it was hard to keep track of what was happening. Information overload is a significant challenge that creates several other challenges for the participants, such as missed messages, redundant messages, wasted e↵orts, and diculty in gathering consensus. I observed some behaviors such as broken utterances and other strategies employed by participants when overwhelmed with the high activity. I use this knowledge to motivate recommendations and suggestions for future redesigns and development of this indispensable tool of the workforce / Master of Science / Group chat facilitates remote collaboration, idea exchanges. It becomes dicult for members of groups to keep up and remain on the same page during long conversations. I conducted experiments where I simulated collaborative group chat conversations to learn about issues and behaviors in a group chat with 5 or 10 members. The experiment participants also filled out a survey after the group chat, describing their challenges and issues with the group chat. Qualitative analyses of the survey data, and the chat conversation gave us several insights. Our results show that participants generally felt that there were too many messages. A ma- jority of the participants found it was hard to keep track of what was happening. Information overload is a significant challenge that creates several other problems for the participants, such as missed messages, repeated messages, wasted e↵orts, and diculty in obtaining agree- ment. I observed some behaviors and strategies used by the participants when overwhelmed with too many messages. I use this knowledge to motivate recommendations and suggestions for future redesigns and development of this indispensable tool of the workforce.

Les écrits de Georges Bataille gravitent autour de l’expérience « intérieure » — expérience vécue là où s’effondre le discours. Cette mise en question du langage donne lieu au paradoxe puisque « dire l’indicible » demeure dans le langage. Face à un tel écueil, il fallait à l’écrivain une stratégie particulière où nous identifions deux méthodes : la dramatisation et le mot glissant. En explorant ces pistes, notre étude se propose de clarifier la stratégie langagière bataillienne (ou écriture « mineure ») pour dégager dans l’œuvre « l’expérience du langage » composée de deux mouvements opposés, à savoir l’émergence du langage et le retour à l’indicible. Pour cela, notre corpus se constitue à partir de textes encore peu connus : La Maison brûlée, Le Petit, Le Mort et La Tombe de Louis XXX. En premier lieu, la dramatisation signifie la procédure de la méditation et le genre dramatique, la fiction opérant dans les deux cas. L’avant-texte de La Maison brûlée, scénario d’un film jamais tourné, présente ainsi dans sa genèse les techniques de la monstration qui dramatisent le mouvement descendant de la chute et de la matière basse. Ensuite, le mot glissant est illustré par le terme « silence », prononcé pour annoncer sa propre mort. Ce mouvement de glissement s’observe dans Le Petit, à travers le style fragmentaire ou les signes de ponctuation. D’ailleurs, pour finir, ce glissement, dont nous interrogeons la consistance, se révèle intrinsèque au présent linguistique en jeu dans Le Mort et La Tombe de Louis XXX. Car l’écriture de Bataille met en scène l’instant présent, cristallisant le passage du discours à l’indicible. / Georges Bataille’s writing gravitates towards, what he calls, the ‘inner’ experience, an experience in which discourse breaks down. Thus, the language, generally denounced, leads to a paradox as long as it remains the language used to ‘speak the unspeakable’. This aporia compels Bataille to devise original writing strategies that are embodied in two methods—dramatization and the ‘slippery word’ (le mot glissant). Considering this, our study clarifies his linguistic strategies (or ‘minor’ writing) to reach his ‘experience of language’, which consists of two opposite movements: the emergence of language and the return to the unspeakable. To this end, our corpus is based on La Maison brûlée, Le Petit, Le Mort and La Tombe de Louis XXX, texts which are still little-known. In Bataille’s work, the term ‘dramatization’ refers to a specific procedure of contemplation and to the drama; fiction participates in both. In particular, the avant-texte of La Maison brûlée, an abandoned movie script, includes techniques for the onscreen projection of images of falling that use both characters and ‘base material’ (matière basse). The second method, the slippery word, is exemplified by the term ‘silence’, which is pronounced only to announce its own death. This movement of the slippery word can be observed in Le Petit, with its fragmentary style or punctuation marks. Moreover, as analysed, the slipping motion turns out to be intrinsic to the present tense, as observed in Le Mort et La Tombe de Louis XXX. Bataille’s writings depict the present moment, crystallizing the passage from the discourse to the unspeakable.

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 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 synchronous textual discussion, especially on handheld devices. <br /> <br /> One element of interaction is gesture, seen as a natural way of conversing. Attaining some level of interaction naturalism requires improving synchronous communication spontaneity, partly achieved by enhancing input mechanisms. To enhance input mechanisms for interactive text-based chat on mobile devices, 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.<br /> <br /> This thesis presents a text only IM system built on 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.<br /> <br /> A hybrid quantitative and qualitative approach was taken to enable data triangulation. Results from experimental trials show that an 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.

En años recientes, el uso de tabletas y teléfonos o dispositivos inteligentes ha incrementado continuamente gracias a la facilidad y disponibilidad de acceso a la información, entretenimiento y comunicación que ofrecen con su creciente variedad de aplicativos y especialmente su acceso a internet. A diferencia de computadoras o notebooks, estos dispositivos tienen tecnologías para mejorar la usabilidad para personas con dificultades visuales que también pueden ser utilizadas para crear nuevos aplicativos de asistencia sin la necesidad de aparatos externos. Esto genera oportunidades para un desarrollo inclusivo que mantiene la misma portabilidad. Sin embargo, estos dispositivos principalmente usan una pantalla táctil y aún entre sus tecnologías incorporadas, no tienen medios para ingresar datos que sean permitan que personas con ceguera ingresen información por otros medios que no sean su voz o un complejo teclado QWERTY. En este artículo, proponemos el uso de una solución adaptativa que permite al usuario usar la misma pantalla táctil como una alternativa para ingresar datos al simular un teclado Braille y demostramos su uso, además de tecnologías de lector de texto, con una aplicación que permite que una persona ciega chatee mediante mensajes instantáneos.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.