paulo silva | Imperial College London (original) (raw)
Papers by paulo silva
In order for agents and humans to leverage the growing wealth of heterogeneous information and se... more In order for agents and humans to leverage the growing wealth of heterogeneous information and services on the web, increasingly, they need to understand the information that is delivered to them. In the simplest case, an agent or human is retrieving "look-up" information and would benefit from having access to provenance information concerning recency, source authoritativeness, etc. In more complicated situations where information is manipulated before it is returned as an answer, agents and humans would benefit from understanding the derivations and assumptions used. When services are involved, users and agents also would benefit from understanding what actions could be or were executed on the user's behalf. In this paper, we introduce a strategy for registering information sources and question answering systems providing support for implementing distributed and cooperative web services. In this paper, we describe the inference web infrastructure that supports explanations in distributed environments such as the web and describe the elements of its registry.
GRAVITAÇÃO UNIVERSAL -3 QUESTÕES 21 TEMPERATURA, DILATAÇÃO E TRANSMISSÃO DO CALOR -6 QUESTÕES 22 ... more GRAVITAÇÃO UNIVERSAL -3 QUESTÕES 21 TEMPERATURA, DILATAÇÃO E TRANSMISSÃO DO CALOR -6 QUESTÕES 22 COMPORTAMENTO DOS GASES IDEAIS -8 QUESTÕES 24 CALORIMETRIA, MUDANÇA DE FASE E 1ª LEI DA TERMODINÂMICA -11 QUESTÕES 26 ONDAS -18 QUESTÕES 29 ÓPTICA -19 QUESTÕES 33 CARGA ELÉTRICA, ELETRIZAÇÃO E LEI DE COULOMB -9 QUESTÕES 38 CAMPO ELÉTRICO -4 QUESTÕES 40 LEIS DE OHM, CORRENTE E POTÊNCIA ELÉTRICA -7 QUESTÕES 41 ASSOCIAÇÃO DE RESISTORES E CIRCUITOS -9 QUESTÕES 42 CAMPO MAGNÉTICO -7 QUESTÕES 44 FORÇA MAGNÉTICA -9 QUESTÕES 46 LEI DE FARADAY E LENZ -7 QUESTÕES 49 ESPECTRO ELETROMAGNÉTICO -3 QUESTÕES 51 FÍSICA MODERNA -10 QUESTÕES 52 GABARITO POR ASSUNTO E FORMULÁRIO 54 www.fisicanovestibular.com.br 3 COMENTÁRIOS Rodrigo Penna 1ª ETAPA DO VESTIBULAR DA UFMG "A prova da Primeira Etapa tem por objetivo avaliar o candidato quanto ao conhecimento e à compreensão de conceitos fundamentais da Física e à aplicação desses conceitos na interpretação de fenômenos naturais, de fatos da vida cotidiana, de experimentos simples e de aplicações tecnológicas. Nessa etapa, o tratamento dos temas será mais conceitual e qualitativo que matemático e quantitativo." Trecho do programa da UFMG de 2009. Obs: algumas questões foram classificadas em mais de uma parte do programa. E a classificação pode ser diferente, variando conforme a interpretação pessoal.
Model-Based User Interface Development Environments (MBUIDEs) provide a context within which user... more Model-Based User Interface Development Environments (MBUIDEs) provide a context within which user interface declarative models can be constructed and related, as part of the user interface design process. This paper provides a review of MB-UIDE technologies. A framework for describing the elements of a MB-UIDE is presented. A representative collection of 14 MBUIDEs are selected, described in terms of the framework, compared and analysed from the information available in the literature. The framework can be used as an introduction to the MB-UIDE technology since it relates and provides a description for the terms used in MB-UIDE papers.
IEEE Transactions on Wireless Communications, 2006
The MC-CDMA signals (Multicarrier Coded Division Multiple Access) have strong envelope fluctuatio... more The MC-CDMA signals (Multicarrier Coded Division Multiple Access) have strong envelope fluctuations which make them very prone to nonlinear effects. These effects can be both intentional (such as the ones inherent to a nonlinear signal processing for reducing the envelope fluctuations) or not (such as the ones inherent to a nonlinear power amplification).
Plant Cell, 2003
When plants, algae, and cyanobacteria are exposed to excessive light, especially in combination w... more When plants, algae, and cyanobacteria are exposed to excessive light, especially in combination with other environmental stress conditions such as extreme temperatures, their photosynthetic performance declines. A major cause of this photoinhibition is the light-induced irreversible photodamage to the photosystem II (PSII) complex responsible for photosynthetic oxygen evolution. A repair cycle operates to selectively replace a damaged D1 subunit within PSII with a newly synthesized copy followed by the light-driven reactivation of the complex. Net loss of PSII activity occurs (photoinhibition) when the rate of damage exceeds the rate of repair. The identities of the chaperones and proteases involved in the replacement of D1 in vivo remain uncertain. Here, we show that one of the four members of the FtsH family of proteases (cyanobase designation slr0228) found in the cyanobacterium Synechocystis sp PCC 6803 is important for the repair of PSII and is vital for preventing chronic photoinhibition. Therefore, the ftsH gene family is not functionally redundant with respect to the repair of PSII in this organism. Our data also indicate that FtsH binds directly to PSII, is involved in the early steps of D1 degradation, and is not restricted to the removal of D1 fragments. These results, together with the recent analysis of ftsH mutants of Arabidopsis, highlight the critical role played by FtsH proteases in the removal of damaged D1 from the membrane and the maintenance of PSII activity in vivo.
A Prova de Redação propõe ao candidato uma temática divulgada pela mídia brasileira nos últimos a... more A Prova de Redação propõe ao candidato uma temática divulgada pela mídia brasileira nos últimos anos que traz impactos sociais, econômicos e culturais ao nosso país: o movimento imigratório.
In order for agents and humans to leverage the growing wealth of heterogeneous information and se... more In order for agents and humans to leverage the growing wealth of heterogeneous information and services on the web, increasingly, they need to understand the information that is delivered to them. In the simplest case, an agent or human is retrieving "look-up" information and would benefit from having access to provenance information concerning recency, source authoritativeness, etc. In more complicated situations where information is manipulated before it is returned as an answer, agents and humans would benefit from understanding the derivations and assumptions used. When services are involved, users and agents also would benefit from understanding what actions could be or were executed on the user's behalf. In this paper, we introduce a strategy for registering information sources and question answering systems providing support for implementing distributed and cooperative web services. In this paper, we describe the inference web infrastructure that supports explanations in distributed environments such as the web and describe the elements of its registry.
GRAVITAÇÃO UNIVERSAL -3 QUESTÕES 21 TEMPERATURA, DILATAÇÃO E TRANSMISSÃO DO CALOR -6 QUESTÕES 22 ... more GRAVITAÇÃO UNIVERSAL -3 QUESTÕES 21 TEMPERATURA, DILATAÇÃO E TRANSMISSÃO DO CALOR -6 QUESTÕES 22 COMPORTAMENTO DOS GASES IDEAIS -8 QUESTÕES 24 CALORIMETRIA, MUDANÇA DE FASE E 1ª LEI DA TERMODINÂMICA -11 QUESTÕES 26 ONDAS -18 QUESTÕES 29 ÓPTICA -19 QUESTÕES 33 CARGA ELÉTRICA, ELETRIZAÇÃO E LEI DE COULOMB -9 QUESTÕES 38 CAMPO ELÉTRICO -4 QUESTÕES 40 LEIS DE OHM, CORRENTE E POTÊNCIA ELÉTRICA -7 QUESTÕES 41 ASSOCIAÇÃO DE RESISTORES E CIRCUITOS -9 QUESTÕES 42 CAMPO MAGNÉTICO -7 QUESTÕES 44 FORÇA MAGNÉTICA -9 QUESTÕES 46 LEI DE FARADAY E LENZ -7 QUESTÕES 49 ESPECTRO ELETROMAGNÉTICO -3 QUESTÕES 51 FÍSICA MODERNA -10 QUESTÕES 52 GABARITO POR ASSUNTO E FORMULÁRIO 54 www.fisicanovestibular.com.br 3 COMENTÁRIOS Rodrigo Penna 1ª ETAPA DO VESTIBULAR DA UFMG "A prova da Primeira Etapa tem por objetivo avaliar o candidato quanto ao conhecimento e à compreensão de conceitos fundamentais da Física e à aplicação desses conceitos na interpretação de fenômenos naturais, de fatos da vida cotidiana, de experimentos simples e de aplicações tecnológicas. Nessa etapa, o tratamento dos temas será mais conceitual e qualitativo que matemático e quantitativo." Trecho do programa da UFMG de 2009. Obs: algumas questões foram classificadas em mais de uma parte do programa. E a classificação pode ser diferente, variando conforme a interpretação pessoal.
Model-Based User Interface Development Environments (MBUIDEs) provide a context within which user... more Model-Based User Interface Development Environments (MBUIDEs) provide a context within which user interface declarative models can be constructed and related, as part of the user interface design process. This paper provides a review of MB-UIDE technologies. A framework for describing the elements of a MB-UIDE is presented. A representative collection of 14 MBUIDEs are selected, described in terms of the framework, compared and analysed from the information available in the literature. The framework can be used as an introduction to the MB-UIDE technology since it relates and provides a description for the terms used in MB-UIDE papers.
IEEE Transactions on Wireless Communications, 2006
The MC-CDMA signals (Multicarrier Coded Division Multiple Access) have strong envelope fluctuatio... more The MC-CDMA signals (Multicarrier Coded Division Multiple Access) have strong envelope fluctuations which make them very prone to nonlinear effects. These effects can be both intentional (such as the ones inherent to a nonlinear signal processing for reducing the envelope fluctuations) or not (such as the ones inherent to a nonlinear power amplification).
Plant Cell, 2003
When plants, algae, and cyanobacteria are exposed to excessive light, especially in combination w... more When plants, algae, and cyanobacteria are exposed to excessive light, especially in combination with other environmental stress conditions such as extreme temperatures, their photosynthetic performance declines. A major cause of this photoinhibition is the light-induced irreversible photodamage to the photosystem II (PSII) complex responsible for photosynthetic oxygen evolution. A repair cycle operates to selectively replace a damaged D1 subunit within PSII with a newly synthesized copy followed by the light-driven reactivation of the complex. Net loss of PSII activity occurs (photoinhibition) when the rate of damage exceeds the rate of repair. The identities of the chaperones and proteases involved in the replacement of D1 in vivo remain uncertain. Here, we show that one of the four members of the FtsH family of proteases (cyanobase designation slr0228) found in the cyanobacterium Synechocystis sp PCC 6803 is important for the repair of PSII and is vital for preventing chronic photoinhibition. Therefore, the ftsH gene family is not functionally redundant with respect to the repair of PSII in this organism. Our data also indicate that FtsH binds directly to PSII, is involved in the early steps of D1 degradation, and is not restricted to the removal of D1 fragments. These results, together with the recent analysis of ftsH mutants of Arabidopsis, highlight the critical role played by FtsH proteases in the removal of damaged D1 from the membrane and the maintenance of PSII activity in vivo.
A Prova de Redação propõe ao candidato uma temática divulgada pela mídia brasileira nos últimos a... more A Prova de Redação propõe ao candidato uma temática divulgada pela mídia brasileira nos últimos anos que traz impactos sociais, econômicos e culturais ao nosso país: o movimento imigratório.