fashion industry in Hong Kong : a case study : Sparkle / by Choi Hung Wai, Ricky. / Bibliography : leaves [43] - 44 / Thesis (M.B.A.)--Chinese University of Hong Kong, 1984

Notre perception du monde est multimodale. Les différents sens (vision, audition, tactile, etc) sont coordonnés entre eux afin d'accomplir nos tâches quotidiennes. Dans le cas où un organe des sens connaît un dysfonctionnement, le système nerveux central est capable de remplacer ou de renforcer l'information manquante en faisant appel à d'autres modalités sensorielles intactes. Le cadre conceptuel de ce remplacement d'un sens par un autre est le paradigme de substitution sensorielle. Cette thèse se situe dans ce contexte et, pour explorer certains aspects de ce paradigme, exploite un dispositif d'électro-stimulation linguale, le Tongue Display Unit (TDU), une matrice de 12x12 électrodes destinée à restituer sous la forme de voltages variables des scènes visuelles sur la langue.L'efficacité de ce dispositif souffre de nombreux problèmes au rang desquels le problème de fading (atténuation) qui correspond à une perte rapide de perception du signal d'électro-stimulation par les sujets et celui de la fusion de perceptions multi-modales qui, nous le verrons, se complique avec l'usage du TDU. Dans cette thèse, nous proposons d'étudier l'effet sur la qualité de perception et sur l'atténuation du signal de l'adjonction au signal image de saccades et de tremblements, processus qui nous ont été inspirés par la vision. Nous étudions également la façon dont les sujets perçoivent un signal image en cas de multi-modalité perceptive (vision + substitution visuelle sur la langue) et l'effet que produisent des contradictions d'information dans ce contexte.Ce travail met en évidence l'importance de la présence de saccades ou de scintillement dans le signal d'électro-stimulation pour contrer les effets de fading : grâce à ces procédés, même lorsque les stimulations sont longues, les sujets continuent de percevoir correctement le signal image. De plus, les expériences de perception multi-modale et de contradictions nous ont permis de montrer que la perception d'informations de type image par l'intermédiaire du TDU était comparable à celle de la vision. Enfin, nous avons pu mettre en évidence un effet de fusion d'informations contradictoires entre la perception visuelle et linguale, connu dans le cadre de la fusion d'information visuo-auditives sous le nom d'effet Mc Gurck.La compréhension de l'effet de procédés destinés à améliorer la perception dans le cadre de la substitution visuelle et celle de l'importance des effets de fusion multi-modale dégagée au cours de thèse devraient trouver application dans de nombreux domaines où ces effets sont présents ou requis, en particulier dans le domaine émergent de la vision prothétique. / Our perception of the world is by essence multimodal. Various sensory cues (vision, hearing, touch, etc.) are hence integrated to allow us the execution of daily life activities. When one sense organ is missing or impaired, in some circumstances, the central nervous system can replace or reinforce the missing sensory information by using reliable sensory information coming from an other intact sense organ. This doctoral thesis was designed to explore this so-called ‘sensory substitution' concept through the exploitation of a visual-to-tactile sensory substitution device. the Tongue Display Unit (TDU) is made of a 12x12 electro-tactile matrix capable of rendering visual scences on the dorsal part of the tongue.However, the effectiveness of this device suffers from numerous drawbacks among which two main problems : (i) the problem of ‘fading' (mitigation) which corresponds to a rapid loss of perception of electrostimulation signal by the individuals and (ii) the problem of multimodal fusion. In the present work, we propose to investigate these problems and their effects on the quality of perception, by (i) applying some eye-inspired mechanisms (micro-saccades) to the electro-tactile signal on the tongue, (ii) studying how individuals perceive a picture signal with multi-modal perceptual (visual stimulus + substitution on the tongue) and (iii) the effect produced contradictions of information in this context.This work evidence the importance of applying saccades and sparkle mechanisms in electro-tactile signal to resolve the problem of fading especially when stimulation periods are relatively long. Furthermore, the experiments we have conducted on multi-modal perception and contradictions suggested that the perception of image information through the TDU was comparable to that of vision. Finally, we were able to identify a conflicting information fusion effect between visual perception and electrotactile tongue perception. This phenomenon is known as Mc Gurck effect (fusion of visual and auditory information). Understanding the effect of these processes to improve the quality of perception through the visual substitution paradigm and the importance of multi-modal fusion effects during this thesis could be applied in various areas where these effects are present or required, especially in the emerging field of prosthetic vision.

Lanthanide-containing systems have many applications, which extend from the biomedical field to optical images areas. Because of that, such systems have attracted the attention of several research groups around the world. It is indisputable that theoretical tools can provide useful information for the understanding of the phenomena that are not easily explained by using only experimental data. Moreover, the theoretical tools are useful for design new systems. Although several tools for the study of lanthanide complexes have been developed since the early 90 s, their use is still limited on account of these tools not being implemented into a userfriendly, free of charge computational package for the scientific community. In this context, the development of LUMPAC (LUMinescence PACkage) is inserted. With this new tool, we hope to enable experimental research groups to use theoretical tools on projects involving systems that contain lanthanide ions. In this dissertation, the methods implemented into LUMPAC are described in detail, given the user a good understanding of them. A short description on LUMPAC is introduced to provide an overview of the features that are implemented in the package. Furthermore, a detailed manual treating all the modulus of LUMPAC is available as an appendix. The LUMPAC project started in 2008. During its development, the program was applied in many different kinds of study involving lanthanide systems, as will be shown in a chapter of this dissertation. The network of collaboration among the Pople Laboratory with some research groups of prestigious universities allowed all these applications. This way, it is then possible to have an idea about some kinds of study in which the program can be applied. So far, LUMPAC is the only software that enables the study of luminescent properties of lanthanide-containing systems, being available free of charge at the following site: http://www.lumpac.pro.br. / Os sistemas contendo íons lantanídeos apresentam diversas aplicações, as quais se estendem desde a área biomédica até a de imagem ótica. Em decorrência disso, a busca por tais sistemas tem atraído a atenção dos mais diversos grupos de pesquisa em todo o mundo. É incontestável que as ferramentas teóricas podem fornecer informações úteis para o entendimento de fenômenos que não são explicados simplesmente com base em dados experimentais. Além disso, as ferramentas teóricas são úteis para o planejamento de novos sistemas. Apesar de diversas ferramentas para o estudo de compostos lantanídicos terem sido desenvolvidas desde o início da década de 90, o seu uso ainda é limitado devido ao fato dessas ferramentas não estarem implementadas em um pacote computacional de fácil uso e disponível gratuitamente para a comunidade científica. É nesse contexto em que o desenvolvimento do LUMPAC (LUMinescence PACkage) está inserido. Com o LUMPAC espera-se difundir o uso de tais métodos teóricos por grupos de pesquisa, sobretudo os experimentais, que concentram seus esforços em entender e projetar novos dispositivos luminescentes a base de lantanídeos. Nesta dissertação, as metodologias que estão implementadas no LUMPAC encontram-se apresentadas de maneira pormenorizada, conferindo ao usuário do software uma maior transparência com relação aos métodos. Uma descrição geral do LUMPAC é apresentada com a finalidade de fornecer uma ideia geral dos recursos que já estão implementados no pacote. Além do mais, um manual bastante detalhado tratando todos os módulos que compreendem o programa é disponibilizado como anexo. O projeto de desenvolvimento do LUMPAC teve início em 2008. Durante o processo de desenvolvimento do pacote, o programa encontrou uma vasta área de aplicação decorrente da rede de colaboração entre o laboratório Pople com alguns grupos de pesquisa de universidades renomadas do país. Através da apresentação dessas aplicações é possível ter uma ideia acerca dos diversos tipos de estudos em que o programa pode ser aplicado. Até o momento, o LUMPAC é o único software desenvolvido que permite o estudo de propriedades luminescentes de sistemas contendo íons lantanídeos, sendo disponibilizado gratuitamente no seguinte endereço eletrônico: http://www.lumpac.pro.br.