Constellations and the unsupervised learning of graphs

In this paper, we propose a novel method for the unsupervised clustering of graphs in the context of the constellation approach to object recognition. Such method is an EM central clustering algorithm which builds prototypical graphs on the basis of fast matching with graph transformations. Our experiments, both with random graphs and in realistic situations (visual localization), show that our prototypes improve the set median graphs and also the prototypes derived from our previous incremental method. We also discuss how the method scales with a growing number of images.

Augmented and Virtual Reality techniques for footwear

The use of 3D imaging techniques has been early adopted in the footwear industry. In particular, 3D imaging could be used to aid commerce and improve the quality and sales of shoes. Footwear customization is an added value aimed not only to improve product quality, but also consumer comfort. Moreover, customisation implies a new business model that avoids the competition of mass production coming from new manufacturers settled mainly in Asian countries. However, footwear customisation implies a significant effort at different levels. In manufacturing, rapid and virtual prototyping is required; indeed the prototype is intended to become the final product. The whole design procedure must be validated using exclusively virtual techniques to ensure the feasibility of this process, since physical prototypes should be avoided. With regard to commerce, it would be desirable for the consumer to choose any model of shoes from a large 3D database and be able to try them on looking at a magic mirror. This would probably reduce costs and increase sales, since shops would not require storing every shoe model and the process of trying several models on would be easier and faster for the consumer. In this paper, new advances in 3D techniques coming from experience in cinema, TV and games are successfully applied to footwear. Firstly, the characteristics of a high-quality stereoscopic vision system for footwear are presented. Secondly, a system for the interaction with virtual footwear models based on 3D gloves is detailed. Finally, an augmented reality system (magic mirror) is presented, which is implemented with low-cost computational elements that allow a hypothetical customer to check in real time the goodness of a given virtual footwear model from an aesthetical point of view.

Improving kNN multi-label classification in Prototype Selection scenarios using class proposals

Prototype Selection (PS) algorithms allow a faster Nearest Neighbor classification by keeping only the most profitable prototypes of the training set. In turn, these schemes typically lower the performance accuracy. In this work a new strategy for multi-label classifications tasks is proposed to solve this accuracy drop without the need of using all the training set. For that, given a new instance, the PS algorithm is used as a fast recommender system which retrieves the most likely classes. Then, the actual classification is performed only considering the prototypes from the initial training set belonging to the suggested classes. Results show that this strategy provides a large set of trade-off solutions which fills the gap between PS-based classification efficiency and conventional kNN accuracy. Furthermore, this scheme is not only able to, at best, reach the performance of conventional kNN with barely a third of distances computed, but it does also outperform the latter in noisy scenarios, proving to be a much more robust approach.

La aplicación de stop-motion en arquitectura: materia y luz

Se inicia un análisis de los procesos de trabajo de stop-motion porque ayudan a comprender las diferentes escalas en arquitectura donde las maquetas se convierten en futuros prototipos de infraestructuras de edificios o de paisaje. Stop motion es una técnica de animación fotograma a fotograma de objetos estáticos mediante la manipulación de figuras de plastilina en entornos fijos con cambios de luz, color y sonido. Igual que dicha técnica reúne lo mejor del rodaje tradicional -story board, escenografía, fotografía, personajes, iluminación- la animación de maquetas de interiores sintetiza micro-procesos de mayor repercusión -habitaciones con cambios de humedad, de temperatura, de ventilación y de iluminación- incorporando efectos especiales que son procesados digitalmente en post-producción. Se construyen varios prototipos de habitación con parámetros fijos como el tamaño y la posición de la cámara y otros variables como los materiales, los personajes y la iluminación. Representan un mundo en miniatura que intenta aportar un acercamiento sensorial y atmosférico analizando la magia y la fantasía que Junichirô Tanizaki describe en la penumbra de las construcciones tradicionales japonesas y estudiando las imperfecciones de los escenarios que Tim Burton manipula en su películas de animación con una textura que las tecnologías digitales no pueden igualar. El objetivo es utilizar una escala micro para realizar unos modelos interiores donde las condiciones atmosféricas están controladas y reducidas, y tomar datos que se podrían aplicar a un proceso de modelado a escala intermedia para testar prototipos de edificios como el túnel de viento; o, finalmente, a una escala macro con maquetas de un sector de la costa o de un río donde los fenómenos meteorológicos son los protagonistas para simular inundaciones y diseñar futuras medidas de prevención y seguridad.

A multimodal tablet-based interface for designing and reviewing 3D engineering models

The ability to view and interact with 3D models has been happening for a long time. However, vision-based 3D modeling has only seen limited success in applications, as it faces many technical challenges. Hand-held mobile devices have changed the way we interact with virtual reality environments. Their high mobility and technical features, such as inertial sensors, cameras and fast processors, are especially attractive for advancing the state of the art in virtual reality systems. Also, their ubiquity and fast Internet connection open a path to distributed and collaborative development. However, such path has not been fully explored in many domains. VR systems for real world engineering contexts are still difficult to use, especially when geographically dispersed engineering teams need to collaboratively visualize and review 3D CAD models. Another challenge is the ability to rendering these environments at the required interactive rates and with high fidelity. In this document it is presented a virtual reality system mobile for visualization, navigation and reviewing large scale 3D CAD models, held under the CEDAR (Collaborative Engineering Design and Review) project. It’s focused on interaction using different navigation modes. The system uses the mobile device's inertial sensors and camera to allow users to navigate through large scale models. IT professionals, architects, civil engineers and oil industry experts were involved in a qualitative assessment of the CEDAR system, in the form of direct user interaction with the prototypes and audio-recorded interviews about the prototypes. The lessons learned are valuable and are presented on this document. Subsequently it was prepared a quantitative study on the different navigation modes to analyze the best mode to use it in a given situation.

Mobile Web applications

This document presents the work that was elaborated at the company Present Technologies as part of the academic discipline Internship/Industrial Project for the Master’s degree in Informatics and Systems, Software Development branch, at Instituto Superior de Engenharia de Coimbra. The area of the mobile web applications has grown exponentially over the last few years turning it into a very dynamic field where new development platforms and frameworks are constantly emerging. Thus, the internship consisted in the study of two new mobile operating systems, Tizen and Firefox OS, as well as two frameworks for packaging of mobile web applications – Adobe PhoneGap and Appcelerator Titanium. These platforms are in the direct interest of Present Technology since it pretends to use them in its future projects in general and in the Phune Gaming project in particular. Since Television is one of the Present Technologies’ business areas, during the course of the internship it was decided to perform additionally a study of two Smart TV platforms, namely Samsung Smart TV and Opera TV, which was considered as a valuable knowledge for the company. For each of the platforms was performed a study about its architecture, supported standards and the development tools that are provided, nevertheless the focus was on the applications and for this reason a practical case study was conducted. The case studies consisted in the creation of a prototype or packaging of an application, for the case of the packaging tools, in order to prove the feasibility of the applications for the Present Technologies’ needs. The outcome of the work performed during the internship is that it raised the awareness of Present Technology of the studied platforms, providing it with prototypes and written documentation for the platforms’ successful usage in future projects.

Caraterização e modelação do comportamento mecânico da resina fotopolimerizada V-Flash FTI-GN

A utilização de tecnologias de prototipagem em objetos e estruturas do dia-a-dia é cada vez maior. Porém, os componentes que é possível fabricar estão em geral associados a protótipos demonstrativos não funcionais. Para ultrapassar estas limitações têm vindo a ser desenvolvidos novos materiais, procurando a melhoria das suas características mecânicas. A presente dissertação insere-se no projeto Firend®, que se tem vindo a desenvolver numa parceria entre a Academia Militar e outras instituições como o Instituto Superior Técnico e procura avaliar a viabilidade da utilização da técnica de deposição de resina fotopolimerizável por ultra-violeta no fabrico de projéteis para o transporte especial de agentes extintores, procurando caracterizar o desempenho deste material em condições operativas simulativas do disparo real. A pesquisa bibliográfica da presente dissertação baseou-se numa breve introdução aos materiais poliméricos. O trabalho teórico consistiu na modelação numérica através do método dos elementos finitos do ensaio de compressão utilizando o programa Deform® e na respetiva validação do modelo através de comparação dos resultados das simulações com dados experimentais existentes na literatura da especialidade. O trabalho experimental fundamentou-se no fabrico e preparação de provetes através da tecnologia de impressão 3D, na descrição das ferramentas utilizadas e do plano experimental. No final verificou-se a fratura de todos os provetes ensaiados e uma grande dispersão dos resultados, conseguindo-se apenas retirar uma tensão de segurança que não deve ser ultrapassada. De acordo com o estudo realizado o material ensaiado demonstrou-se não ser apropriado para a aplicação pretendida e recomenda-se a avaliação de outros materiais igualmente utilizados pelas técnicas de prototipagem rápida, tais como uma mistura de uma resina polimérica com um outro material com características mecânicas mais adequadas.

Fabrico e ensaio balístico em condições reais de conceito melhorado de um projétil de detonação mecânica

A floresta constitui uma das riquezas naturais com maior valor em todo o planeta, assumindo uma vital importância em termos ambientais e económicos, nomeadamente para Portugal. Neste projeto desenvolve-se um potencial meio de combate a incêndios florestais, com base num conceito inovador e complementar aos atuais meios aplicados no combate a este tipo de flagelo. Este projeto de investigação visa o desenvolvimento de um projétil de detonação mecânica, logo inerte, para aplicação no combate a incêndios florestais, e enquadra-se no âmbito de uma parceria alargada de colaboração em I&D entre a Academia Militar e o Instituto Superior Técnico. O conceito deste produto, ao qual foi atribuído o acrónimo: FIREND, foi, inicialmente, desenvolvido no âmbito de um projeto de I&D da Academia Militar. Neste projeto realiza-se o desenvolvimento final do conceito do produto, incluindo a verificação de aspetos chave no projeto mecânico, seleção e aquisição de materiais e fabrico de protótipos para ensaios balísticos em condições reais. Os resultados de funcionalidade e eficiência são apresentados nas fases estabilidade em voo, impacto com o solo, detonação, projeção e dispersão da carga para o exterior e análise de recuperação dos componentes do FIREND, após utilização. Tendo em conta os resultados obtidos relativos ao funcionamento do FIREND durante o disparo do Obus, voo, impacto no solo e detonação e ainda o estado geral dos componentes após os ensaios, pode-se concluir que se trata de um projeto viável.

Domino's Pizza, Inc., Prototype Franchise Building, Jackson, Michigan, 1986-1988

[Conceptual Sketch], untitled. Ink sketch with blue marker coloring on tracing paper, 18x19 inches [from photographic copy by Lance Burgharrdt]

Domino's Pizza, Inc., Prototype Franchise Building, Jackson, Michigan, 1986-1988

[Conceptual Sketch], untitled. Ink sketch with blue and gray marker coloring on tracing paper, 18 x 19 1/2 inches [from photographic copy by Lance Burgharrdt]

Embassy Prototype for Foreign Buildings Office, Washington, D.C., 1975 (unbuilt project)

[Conceptual Sketch of Ideal Embassy], untitled. Black and orange ink sketch on graph paper, 8 1/2 x 11 inches [from photographic copy by Lance Burgharrdt]

Experimental studies on the accuracy of wax patterns used in investment casting

Investment casting is often used to produce fully functional prototype components from sacrificial patterns. These patterns (prototypes) may be made using specialized rapid prototyping techniques such as stereolithography or three-dimensional printing. When multiple functional prototypes are required, interim tools for making wax patterns are employed. The objective of this research work was to determine the precision and accuracy of wax patterns produced using several prototype tools. Linear contraction was used to determine the accuracy as a function of the wax injection parameters used in low-pressure injection moulding. Wax patterns were produced using polyurethane and silicone rubber tools. It has been shown that the accuracy of patterns from both tools is similar. However, silicone tools produce patterns with much higher contraction than those produced by polyurethane tools. Unconstrained patterns dimensions contracted as much as 3.44 +/- 0.40 per cent and 1.70 +/- 0.60 per cent for silicone and polyurethane tools respectively. The constrained dimensions contracted by 2.20 +/- 0.20 per cent in the case of silicone tools and 1.40 +/- 0.20 per cent in the case of polyurethane tools.

A rapid dietary assessment tool to determine intake of folate was developed and validated

Background and Objective: Estimates of dietary folate intake are currently of considerable interest, but no rapid tools are available to assess dietary intake of folate that are well suited to everyday health promotion activities, We developed and tested the reliability and validity of two prototypes of a rapid dietary assessment tool (a folate intake tool, FIT) to determine dietary intake of folate. Study Design and Setting: Five hundred and sixty eight men and women aged 33-93 years from Perth, Western Australia. Completed one of the two prototypes of the tool and gave a fasting blood sample for measurement of serum folate. A subset (n - 277) of participants completed the same tool on a second occasion 3-6 weeks later. Results: The Pearson correlations (r) between folate score from the tool and serum folate were moderately high for both prototypes (FIT-A r = 0.54-, FIT-B r = 0.49). The folate scores for the two prototypes were similar on repeat testing and correlated strongly (FIT-A r = 0.75; FIT-B r = 0.68). Conclusions: The rapid dietary assessment tool described here, FIT, provides a valid and reliable measurement of dietary intake of folate for both men and women. (c) 2005 Elsevier Inc. All rights reserved.

First development of a polyurethane keratoprosthesis and its Australian connection: An unbeknown episode in the history of artificial cornea

This paper is aimed at establishing a particular chronological priority issue in the convoluted history of artificial cornea. According to existing records, the first keratoprosthesis made from polyurethane was developed by Caldwell and Jacob-Labarre in the late 1980s. This paper demonstrates that in fact the first polyurethane keratoprosthesis was proposed and designed in 1985 by Lawrence Hirst, an Australian ophthalmologist then working in St Louis, USA. The first prototype was manufactured in January 1986 by Thermedics Inc according to Dr Hirst's instructions from Tecoflex, a transparent polyurethane developed by the same company. This keratoprosthesis, which also had a porous skirt, was inserted intralamellarly in a monkey cornea and followed up clinically for about 3 months. There were no significant postoperative complications, and the histology of the explant indicated proper biointegration of the prosthetic skirt within the host stromal tissue. Because of a delay in the manufacture of further prototypes and to Dr Hirst's decision to return to Australia, the project was eventually abandoned. As no report was published on this development, the present paper is entirely based on original documents held in Dr Hirst's archives.

Social identity, self-categorization, and the communication of group norms

We articulate the role of norms within the social identity perspective as a basis for theorizing a number of manifestly communicative phenomena. We describe how group norms are cognitively represented as context-dependent prototypes that capture the distinctive properties of groups. The same process that governs the psychological salience of different prototypes, and thus generates group normative behavior, can be used to understand the formation, perception, and diffusion of norms, and also how some group members, for example, leaders, have more normative influence than others. life illustrate this process across a number of phenomena and make suggestions for future interfaces between the social identity perspective and communication research. We believe that the social identity approach represents a truly integrative force for the communication discipline.