8 research outputs found

    Asynchronous spike event coding scheme for programmable analogue arrays and its computational applications

    Get PDF
    This work is the result of the definition, design and evaluation of a novel method to interconnect the computational elements - commonly known as Configurable Analogue Blocks (CABs) - of a programmable analogue array. This method is proposed for total or partial replacement of the conventional methods due to serious limitations of the latter in terms of scalability. With this method, named Asynchronous Spike Event Coding (ASEC) scheme, analogue signals from CABs outputs are encoded as time instants (spike events) dependent upon those signals activity and are transmitted asynchronously by employing the Address Event Representation (AER) protocol. Power dissipation is dependent upon input signal activity and no spike events are generated when the input signal is constant. On-line, programmable computation is intrinsic to ASEC scheme and is performed without additional hardware. The ability of the communication scheme to perform computation enhances the computation power of the programmable analogue array. The design methodology and a CMOS implementation of the scheme are presented together with test results from prototype integrated circuits (ICs)

    On Evolution of CMOS Image Sensors

    Get PDF

    CMOS nanophotonic sensor with integrated readout system

    Get PDF
    The measurement of nanophotonic sensors currently requires the use of external measuring equipment for their read-out such as an optical spectrum analyzer, spectrophotometer, or detectors. This requirement of external laboratory-based measuring equipment creates a “chip-in-a-lab” dilemma and hinders the use of nanophotonic sensors in practical applications. Making nanophotonic sensors usable in everyday life requires miniaturization of not only the sensor chip itself but also the equipment used for its measurement. In this paper, we have removed the need of external measuring equipment by monolithically integrating 1-D grating structures with a complementary metal-oxide-semiconductor (CMOS) integrated circuit having an array of photodiodes. By doing so, we get a direct electrical read-out of the refractive index changes induced when applying different analytes to grating structures. The gratings are made of CMOS compatible silicon nitride. Employing a nanophotonic sensor made of CMOS compatible material allows fabrication of the integrated sensor chip in a commercial CMOS foundry, enabling mass production for commercialization with low cost. Our results present a significant step toward transforming present laboratory-based nanophotonic sensors into practical portable devices to enable applications away from the analytical laboratory. We anticipate the work will have a major impact on technology for personalized medicine, environmental, and industrial sensing

    The inventory of geological heritage of the state of São Paulo, Brazil: Methodological basis, results and perspectives

    Get PDF
    An inventory of geological sites based on solid and clear criteria is a first step for any geoconservation strategy. This paper describes the method used in the geoheritage inventory of the State of São Paulo, Brazil, and presents its main results. This inventory developed by the geoscientific community aimed to identify geosites with scientific value in the whole state, using a systematic approach. All 142 geosites representative of 11 geological frameworks were characterised and quantitatively evaluated according to their scientific value and risk of degradation, in order to establish priorities for their future management. An online database of the inventory is under construction, which will be available to be easily consulted and updated by the geoscientific community. All data were made available to the State Geological Institute as the backbone for the implementation of a future state geoconservation strategy.The authors acknowledge the Science Without Borders Programme, Process 075/2012, which supported this study and the São Paulo Research Foundation (FAPESP), Process 2011/17261-6. We also thanks C. Mazoca for his help with maps and figures.info:eu-repo/semantics/acceptedVersio

    Asynchronous spike event coding scheme for programmable analogue arrays and its computational applications

    No full text
    This work is the result of the definition, design and evaluation of a novel method to interconnect the computational elements - commonly known as Configurable Analogue Blocks (CABs) - of a programmable analogue array. This method is proposed for total or partial replacement of the conventional methods due to serious limitations of the latter in terms of scalability. With this method, named Asynchronous Spike Event Coding (ASEC) scheme, analogue signals from CABs outputs are encoded as time instants (spike events) dependent upon those signals activity and are transmitted asynchronously by employing the Address Event Representation (AER) protocol. Power dissipation is dependent upon input signal activity and no spike events are generated when the input signal is constant. On-line, programmable computation is intrinsic to ASEC scheme and is performed without additional hardware. The ability of the communication scheme to perform computation enhances the computation power of the programmable analogue array. The design methodology and a CMOS implementation of the scheme are presented together with test results from prototype integrated circuits (ICs).EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Infrared plasmonic filters integrated with an optical and terahertz multi-spectral material

    No full text
    Infrared plasmonic filters, consisting of subwavelength holearrays etched into metal films, exhibit characteristics that aretypically associated with the formation of surface plasmonpolaritons, namely enhanced transmission and wavelengthfiltering of the incident light. In this article, the properties thatdictate the plasmonic response of a material from the optical tothe infrared regime are investigated, followed by the design,simulation, fabrication and characterisation of an infraredplasmonic filter set. Infrared plasmonic filters have also beenintegrated with optical plasmonic filters and a terahertzmetamaterial to create a new hybrid multi-spectral materialthat can filter blue, green, red, near infrared, short waveinfrared and two mid infrared wavelengths whilst simulta-neously absorbing a single terahertz frequency. The multi-spectral material could be integrated with appropriate imagesensors to create a multi-spectral camera capable of operatingat optical, infrared and terahertz wavebands simultaneously

    De jure sacro: a inquisição nas vilas d'El Rei De jure sacro: the inquisition in the villages of the king

    No full text
    Esse artigo tem por objetivo divulgar as denúncias registradas nos Cadernos do Promotor relativos a Minas Gerais, pertencentes ao fundo da Inquisição de Lisboa, depositados no Arquivo Nacional da Torre de Tombo/Portugal, com ênfase nos estudos de caso relativos a São João del-Rei e Tiradentes<br>The purpose of this article is to make known the accusations registered in the Lisbon Inquisition's Cadernos do Promotor (Prosecutor'S Notebooks) and the prosecuted cases pertaining to Minas Gerais, especially the villages of São João del-Rei and Tiradentes. These sources are deposited in Portugal's Arquivo Nacional da Torre de Tombo/Lisbo
    corecore