Browsing by Issue Date, starting with "2008"
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- Decisions with multiple simultaneous goals and uncertain causal effectsPublication . Trigo, Paulo; Coelho, HelderA key aspect of decision-making in a disaster response scenario is the capability to evaluate multiple and simultaneously perceived goals. Current competing approaches to build decision-making agents are either mental-state based as BDI, or founded on decision-theoretic models as MDP. The BDI chooses heuristically among several goals and the MDP searches for a policy to achieve a specific goal. In this paper we develop a preferences model to decide among multiple simultaneous goals. We propose a pattern, which follows a decision-theoretic approach, to evaluate the expected causal effects of the observable and non-observable aspects that inform each decision. We focus on yes-or-no (i.e., pursue or ignore a goal) decisions and illustrate the proposal using the RoboCupRescue simulation environment.
- Mulheres, teatro e religião: o tema da virgindadePublication . Vasques, EugéniaFoi a partir do século XVII que as mulheres passaram a fazer parte das actuações teatrais na Inglaterra a na França. Na Inglaterra, os papéis femininos eram antes representados por jovens actores aprendizes. Na França, uma das actrizes que havia sido integrante da Companhia de Molière, Therese du Parc, conhecida depois como La Champmesle, passou a fazer parte do elenco especializado de Racine e foi a primeira actriz a interpretar o papel de Fedra, da obra homónima de Racine, tornando-se uma das principais actrizes da Commédie Française. Em Portugal, embora se infira dos documentos que pode ter havido mulheres a representar as peças de Gil Vicente (1465?-1536?), incluindo, provavelmente, a sua filha Paula Vicente, a verdade é que só temos conhecimento de actrizes portuguesas, isto é, actrizes não amadoras (em teatros particulares), a partir do século XVIII. Porém, desde o século anterior, existiram também relevantes dramaturgas, sobretudo nos conventos, período marcado pela influência directa do popular teatro espanhol «de capa e espada». Falar ou escrever sobre temas religiosos era, em virtude do acompanhamento e tutoria religiosos dos conventos, uma forma mais “segura” de expressão. Os casos mais notórios de freiras que escreveram teatro nessa altura em Portugal, em castelhano, a língua da cultura da Península, sob influência dos grandes poetas espanhóis Gôngora e Calderón, foram Sóror Maria do Céu e Soror Violante do Céu. Analisa-se um dos mais relevantes exemplos de dramaturgia europeia centrada no arquétipo da Virgem Guerreira e insubmissa: L’Annonce Faite à Marie, de Paul Claudel (França, 1868-1955).
- Suffix Arrays: A competitive choice for fast Lempel-Ziv CompressionPublication . J. Ferreira, Artur; Oliveira, Arlindo L.; Figueiredo, MarioLossless compression algorithms of the Lempel-Ziv (LZ) family are widely used in a variety of applications. The LZ encoder and decoder exhibit a high asymmetry, regarding time and memory requirements, with the former being much more demanding. Several techniques have been used to speed up the encoding process; among them is the use of suffix trees. In this paper, we explore the use of a simple data structure, named suffix array, to hold the dictionary of the LZ encoder, and propose an algorithm to search the dictionary. A comparison with the suffix tree based LZ encoder is carried out, showing that the compression ratios are roughly the same. The ammount of memory required by the suffix array is fixed, being much lower than the variable memory requirements of the suffix tree encoder, which depends on the text to encode. We conclude that suffix arrays are a very interesting option regarding the tradeoff between time, memory, and compression ratio, when compared with suffix trees, that make them preferable in some compression scenarios.
- Estereótipos de género, sexo e violência na publicidade em PortugalPublication . Pereira, Francisco José Costa; Verissimo, Jorge; Correia, Maria do RosárioIdentificar e Analisar a presença de cenas de sexo, violência e estereótipos de género na publicidade emitida em Portugal. Pretende-se compreender como a publicidade em Portugal explora as dimensões referidas: Ao nível do sexo Procura-se compreender como a publicidade constrói as suas mensagens fazendo apelo a cenas que de uma forma explícita ou implícita envolvam imagens ou linguagem de carácter sexual. Ao nível da violência Procura-se compreender como a publicidade introduz nos seus conteúdos a agressão ou violência, seja ela física, verbal ou gratuita. Ao nível dos estereótipos de género Procura-se compreender como o homem e a mulher são retratados na publicidade, se é feito apelo a papéis de género diferenciados ou não. Se ao homem se atribuem os papéis sociais, exteriores, de status e se à mulher se atribuem os papéis de dona de casa, mãe e no interior de uma casa. Perceber se para além destas diferenças se o homem ou a mulher são descriminados um em relação ao outro, se um se subordina ao outro ou não.
- Tuneable micro- and nano-periodic structures in urethane/urea networksPublication . Godinho, M. H.; Figueirinhas, J. L.; Brogueira, Pedro; Teixeira, PauloMicro- and nano-patterned materials are of great importance for the design of new nanoscale electronic, optical and mechanical devices, ranging from sensors to displays. A prospective system that can support a designed functionality is elastomeric polyurethane thin films with nano- or micromodulated surface structures ("wrinkles"). These wrinkles can be induced on different lengthscales by mechanically stretching the films, without the need for any sophisticated lithographic techniques. In the present article we focus on the experimental control of the wrinkling process. A simple model for wrinkle formation is also discussed, and some preliminary results reported. Hierarchical assembly of these tunable structures paves the way for the development of a new class of materials with a wide range of applications, from electronics to biomedicine.
- Novos media e domesticaçãoPublication . Lopes, Anabela de SousaDomesticação é uma metáfora que traduz o jogo de forças que se estabelece entre diferentes meios de comunicação e os seus utilizadores. Apesar de podermos assumir que o indivíduo domestica os media e que estes domesticam o indivíduo, importa perguntar se os chamados novos media obrigam a novas formas de domesticação e a um efectivo reforço da responsabilidade individual da sua utilização.
- Management of dynamic production networks from a critical chain perspectivePublication . Tenera, Alexandra; Abreu, AntónioCollaborative networks are typically assumed to bring clear benefits and competitive advantage to the participating members. However, as the networks are typically formed by heterogeneous and autonomous enterprises, the development of methodologies that facilitates the management process is an important element for the wide adoption of this paradigm. Departing from a brief presentation of Critical Chain Project Management Concepts, this paper introduces an approach of these concepts to collaborative networks and discusses its potential application in the context of a dynamic production networks. Finally, experimental results based on data from a network in construction industry are presented.
- New trends in advertising researchPublication . Pereira, Francisco José Costa; Veríssimo, Jorge Domingos Carapinha; Neijens, PeterNew Trends in Advertising Research presents a wide spectre recent and works whose aim is to demonstrate how advertising works drawing special attention to the role of culture, the advertising content, new technologies, and the way advertising agencies develop appropriate practices to make advertising campaigns efficient. The book has 29 chapters framed in five parts. The first part - How advertising works - presents six studies that show dimensions of messages conception, the organization of motivations, the imply-benefit attributes, and how celebrities can contribute to the effectiveness of messages. The second part discusses effects of Product Placement and Sponsorship. The third part - Advertising & Culture – presents six studies that show the way in which cultures and subcultures may influence advertising and advertising effects. The fourth part on new Technologies of Information and Communication(TIC) includes five studies on new advertising platforms. The last part presents seven studies on Content and Context Factors in Advertising. The book addresses itself to the advertising professionals, to advertising communication researchers, as well as to graduate and undergraduate students of advertising and communication, who want to be informed about the last research within these areas.
- Design of distributed fault tolerant control systemsPublication . Costa, José Sá da; Mendes, Mário J. G. C.When dealing with large-scale complex networked control systems, designing FDI/FTC systems is a very difficult task due to the large number of sensors and actuators spatially distributed and networked connected. Despite the research effort on developing FTC systems for NCS most of these developments still being designed globally leading to centralized FTC solutions inadequate to NCS or, assume the communication network and the process itself as two different entities loosing the potentiality of the integrated design. The FDI/FTC design method presented in this paper is able to use simple and verifiable principles coming mainly from a decentralized design, based on causal modelling partitioning of the NCS and distributed computing using multi-agents systems, allowing the use of well established FDI/FTC methodologies, or new ones, developed taking into account the NCS specificities. The design methodology is made easy using a FTCNS-MAS toolbox introduced in this paper.
- Non-selective optical wavelength-division multiplexing devices based on a-SiC:H multilayer heterostucturesPublication . Vieira, Manuela; Fernandes, Miguel; Louro, Paula; Vieira, Manuel; Barata, Manuel; Fantoni, AlessandroIn this paper we present results on the optimization of multilayered a-SiC:H heterostructures for wavelength-division (de) multiplexing applications. The non selective WDM device is a double heterostructure in a glass/ITO/a-SiC:H (p-i-n) /a-SiC:H(-p) /a-Si:H(-i')/a-SiC:H (-n')/ITO configuration. The single or the multiple modulated wavelength channels are passed through the device, and absorbed accordingly to its wavelength, giving rise to a time dependent wavelength electrical field modulation across it. The effect of single or multiple input signals is converted to an electrical signal to regain the information (wavelength, intensity and frequency) of the incoming photogenerated carriers. Here, the (de) multiplexing of the channels is accomplished electronically, not optically. This approach offers advantages in terms of cost since several channels share the same optical components; and the electrical components are typically less expensive than the optical ones. An electrical model gives insight into the device operation.