Stacked photo-sensing devices based on SiC alloys A non-pixelled architecture for imagers and demultiplexing devices

In this review paper different designs based on stacked p-i'-n-p-i-n heterojunctions are presented and compared with the single p-i-n sensing structures. The imagers utilise self-field induced depletion layers for light detection and a modulated laser beam for sequential readout. The effect of the sensing element structure, cell configurations (single or tandem), and light source properties (intensity and wavelength) are correlated with the sensor output characteristics (light-to-dark sensivity, spatial resolution, linearity and S/N ratio). The readout frequency is optimized showing that scans speeds up to 104 lines per second can be achieved without degradation in the resolution. Multilayered p-i'-n-p-i-n heterostructures can also be used as wavelength-division multiplexing /demultiplexing devices in the visible range. Here the sensor element faces the modulated light from different input colour channels, each one with a specific wavelength and bit rate. By reading out the photocurrent at appropriated applied bias, the information is multiplexed or demultiplexed and can be transmitted or recovered again. Electrical models are present to support the sensing methodologies.

Educação inclusiva : necessidades de formação de professores do 1º ciclo do ensino básico em meio rural

Este estudo, de natureza qualitativa, visa em primeiro lugar a identificação de necessidades de formação contínua de docentes do 1º ciclo do ensino básico, decorrentes da inclusão de alunos com necessidades educativas especiais (N.E.E.) em escolas de meio rural. Pretende ainda criar linhas orientadoras para a construção de um dispositivo de formação contínua que possa contribuir para o desenvolvimento de capacidades, atitudes e conhecimentos relacionados com a inclusão de alunos com N.E.E. Utilizámos a entrevista semi - directiva, de forma a conhecer a percepção que os professores têm sobre as suas necessidades formativas e recorremos a observações naturalistas, de modo a identificar necessidades decorrentes da prática, através da análise de situações reais de aprendizagem em salas de aula inclusivas. Foram entrevistados 8 professores, tendo sido observadas as aulas de dois desses professores. A partir do cruzamento dos dados obtidos por ambas as técnicas, identificámos um conjunto de preocupações, dificuldades, aspirações/desejos relacionados com a inclusão e ainda carências formativas relacionadas com as N.E.E. As entrevistas permitiram-nos explorar, de uma forma geral, a percepção que os professores tinham das suas necessidades, ou seja as necessidades percebidas, enquanto que as observações nos possibilitaram a identificação das necessidades da prática, necessidades inferidas. No presente estudo, foi possível concluir que as observações constituem um meio privilegiado para a identificação de necessidades de formação, ao nível da prática pedagógica de uma sala de aula, na medida em que os professores, nas entrevistas, não expressaram algumas das dificuldades observadas e não identificaram um conjunto de carências formativas que a análise da observação sugere. Partindo dos resultados obtidos, foi possível enumerar as principais necessidades de formação contínua decorrentes da inclusão e propor um dispositivo de formação contínua, apoiado na observação e supervisão, que julgamos poder dar resposta às necessidades formativas dos professores encontradas no presente estudo.

A Flexible Architecture for the Computation of Direct and Inverse Transforms in H.264/AVC Video Codecs

A new high throughput and scalable architecture for unified transform coding in H.264/AVC is proposed in this paper. Such flexible structure is capable of computing all the 4x4 and 2x2 transforms for Ultra High Definition Video (UHDV) applications (4320x7680@ 30fps) in real-time and with low hardware cost. These significantly high performance levels were proven with the implementation of several different configurations of the proposed structure using both FPGA and ASIC 90 nm technologies. In addition, such experimental evaluation also demonstrated the high area efficiency of theproposed architecture, which in terms of Data Throughput per Unit of Area (DTUA) is at least 1.5 times more efficient than its more prominent related designs(1).

Representações dos técnicos de intervenção precoce sobre as famílias e práticas de IP em contexto rural e urbano

O presente estudo visou caraterizar as representações que técnicos de intervenção precoce têm sobre famílias que vivem em meio rural e em meio urbano que recebem apoio das equipas. Foram realizadas entrevistas semi-diretivas, os participantes e entrevistados foram dez docentes com intervenção educativa nas equipas, cinco em apoio direto a famílias de meio rural e cinco a realizar intervenções com famílias de meio urbano. Deste estudo resultaram vários dados qualitativos que depois de analisados e discutidos, levaram a diversas conclusões que vem dar respostas às questões e problemática iniciais. As famílias inseridas nestes contextos têm características que as diferenciam; habilitações, recursos, necessidades e comportamentos em comunidade. Tem aspetos culturais que influenciam as suas atitudes, participação e autonomia e são ou não decisivas no desenvolvimento da criança. Em contexto rural as famílias apresentam um maior número de necessidades comparativamente às famílias de meio urbano. As maiores necessidades das famílias em contexto rural situam-se nas questões financeiras, de formação e apoio técnico e especializado. As maiores necessidades das famílias de contexto urbano situam-se ao nível do fraco apoio familiar e das redes sociais. As necessidades comuns situam-se nas necessidades de informação e promoção da autonomia e competências parentais. As visitas e intervenções domiciliares podem permitir melhorar a identificação das necessidades e recursos das famílias e compreender melhor os critérios de referência de algumas crianças. As oportunidades de aprendizagem são maiores nestes encontros em domicílio, estão presentes em muitos casos, elementos da família alargada, que muitas vezes tem um papel fundamental na educação e estimulação destas crianças. Os docentes de IP em intervenção em contexto urbano, comparativamente com os docentes inseridos em contexto rural, apoiam famílias que na generalidade abrangem áreas profissionais mais vantajosas financeiramente. Estas famílias terão á partida melhores condições para aceder a mais recursos e apoios. Nos dois contextos existe uma necessidade comum, falta de informação e alguma autonomia e competências parentais em relação ao crescimento das crianças. A realização de iii encontros de pais ou criação de grupos de pais que tenham por base a partilha de experiencias e informação, estão planeadas mas não são uma realidade nestas equipas. Nas práticas de qualidade, o profissional deve atuar nos contextos naturais como, a família, ou a comunidade, mas pode incluir também rotinas, brincadeiras, festas etc. cenários que facilitem o dia-a-dia. As famílias têm contextos e rotinas próprias que os profissionais devem identificar, os dados que recolhemos indicam essa necessidade de proceder a avaliação mais atenta das necessidades das famílias. As práticas recomendadas e o enquadramento legislativo são tidos em conta pelos docentes e profissionais das equipas, os recursos documentais são na sua maioria comuns, a todas as equipas participantes, seguindo as orientações e documentos/minutas facultadas pela comissão coordenadora do SNIPI (Sistema Nacional de Intervenção Precoce na Infância) Apesar das recomendações teóricas para práticas de qualidade centradas na família, verificamos que estas fazem parte das preocupações destes docentes, mas nem sempre são implementadas. A problemática da criança parece ser ainda o ponto mais importante dos programas e planos de intervenção e mesmo o critério decisivo para delinear a duração e frequência das intervenções, seja em contexto urbano ou rural. - ABSTRACT This study aimed to characterize the families of rural and urban areas that receive support from Early Intervention Teams. It has been proposed yet whether professionals IP suit their practices to the characteristics of these families and communities integrated in different cultural contexts. Interviews were conducted semidirective, participants were ten respondents and teachers with educational intervention teams, five in direct support to families in rural areas and five interventions with families in urban areas. This study resulted in a number of qualitative data that then analyzed and discussed, led to several conclusions that comes to answer the questions and problems early. The families included in these contexts have characteristics that differentiate them; qualifications, resources, needs and behaviors in the community. Has cultural aspects that influence their attitudes, participation and autonomy and are not decisive in the development of the child. In the rural households have a greater number of needs compared to urban families. The greatest needs of families in rural settings are located in financial matters, training and technical support and expertise. The greatest needs of the urban households are located at the level of weak family support and social networks. Common needs lie in information needs and promoting autonomy and parenting skills. The home visits and interventions may allow improved identification of needs and resources of families and understand the benchmarks of some children. Learning opportunities are greater in these meetings at home, are present in many cases, elements of the extended family, which often plays a key role in education and stimulation of these children. Teachers IP intervention in the urban compared with rural teachers placed in context, support families in general include professional areas more financially advantageous. These families will have better starting conditions for access to more resources and support. In both contexts there is a common need, lack of information and some autonomy and parenting skills in relation to the growth of children. The meetings of parents or creating parent groups that are based on the sharing of information and experiences are planned but are not a reality in these teams. In quality practices, the professional must act in natural contexts like the family or the community, but may also include routines, jokes, and parties’ etc. scenarios that v facilitate the day-to-day. Families have their own contexts and routines that professionals should identify, collect the data indicate that the need for more careful assessment of the needs of families. Best practices and legislative environment are taken into account by teachers and professional teams, the documentary resources are mostly common to all participating teams, following the guidelines and documents / drafts provided by the coordinating committee SNIPI (National Intervention Early Childhood) Despite the theoretical recommendations for quality practices family-centered, we see that these are part of the concerns of teachers, but are not always implemented. The issue of child seems to be still the most important programs and plans and even the decisive criterion for delineating the duration and frequency of interventions whether in urban or rural.

Scalable Unified Transform Architecture for Advanced Video Coding Embedded Systems

A novel high throughput and scalable unified architecture for the computation of the transform operations in video codecs for advanced standards is presented in this paper. This structure can be used as a hardware accelerator in modern embedded systems to efficiently compute all the two-dimensional 4 x 4 and 2 x 2 transforms of the H.264/AVC standard. Moreover, its highly flexible design and hardware efficiency allows it to be easily scaled in terms of performance and hardware cost to meet the specific requirements of any given video coding application. Experimental results obtained using a Xilinx Virtex-5 FPGA demonstrated the superior performance and hardware efficiency levels provided by the proposed structure, which presents a throughput per unit of area relatively higher than other similar recently published designs targeting the H.264/AVC standard. Such results also showed that, when integrated in a multi-core embedded system, this architecture provides speedup factors of about 120x concerning pure software implementations of the transform algorithms, therefore allowing the computation, in real-time, of all the above mentioned transforms for Ultra High Definition Video (UHDV) sequences (4,320 x 7,680 @ 30 fps).

High Performance Multi-Standard Architecture for DCT Computation in H.264/AVC High Profile and HEVC Codecs

A new high performance architecture for the computation of all the DCT operations adopted in the H.264/AVC and HEVC standards is proposed in this paper. Contrasting to other dedicated transform cores, the presented multi-standard transform architecture is supported on a completely configurable, scalable and unified structure, that is able to compute not only the forward and the inverse 8×8 and 4×4 integer DCTs and the 4×4 and 2×2 Hadamard transforms defined in the H.264/AVC standard, but also the 4×4, 8×8, 16×16 and 32×32 integer transforms adopted in HEVC. Experimental results obtained using a Xilinx Virtex-7 FPGA demonstrated the superior performance and hardware efficiency levels provided by the proposed structure, which outperforms its more prominent related designs by at least 1.8 times. When integrated in a multi-core embedded system, this architecture allows the computation, in real-time, of all the transforms mentioned above for resolutions as high as the 8k Ultra High Definition Television (UHDTV) (7680×4320 @ 30fps).

A Compact and Scalable RNS Architecture

Conferência: IEEE 24th International Conference on Application-Specific Systems, Architectures and Processors (ASAP)- Jun 05-07, 2013

Comparação técnica da conceção/solução de projetos de climatização para um hotel rural

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia com a Especialidade em Energia, Climatização e Refrigeração

An efficient scalable RNS architecture for large dynamic ranges

This paper proposes an efficient scalable Residue Number System (RNS) architecture supporting moduli sets with an arbitrary number of channels, allowing to achieve larger dynamic range and a higher level of parallelism. The proposed architecture allows the forward and reverse RNS conversion, by reusing the arithmetic channel units. The arithmetic operations supported at the channel level include addition, subtraction, and multiplication with accumulation capability. For the reverse conversion two algorithms are considered, one based on the Chinese Remainder Theorem and the other one on Mixed-Radix-Conversion, leading to implementations optimized for delay and required circuit area. With the proposed architecture a complete and compact RNS platform is achieved. Experimental results suggest gains of 17 % in the delay in the arithmetic operations, with an area reduction of 23 % regarding the RNS state of the art. When compared with a binary system the proposed architecture allows to perform the same computation 20 times faster alongside with only 10 % of the circuit area resources.

Performance analysis of a VDFLL GNSS receiver architecture under ionospheric scintillation and multipath conditions

A noncoherent vector delay/frequency-locked loop (VDFLL) architecture for GNSS receivers is proposed. A bank of code and frequency discriminators feeds a central extended Kalman filter that estimates the receiver's position and velocity, besides the clock error. The VDFLL architecture performance is compared with the one of the classic scalar receiver, both for scintillation and multipath scenarios, in terms of position errors. We show that the proposed solution is superior to the conventional scalar receivers, which tend to lose lock rapidly, due to the sudden drops of the received signal power.

Unified transform architecture for AVC, AVS, VC-1 and HEVC high-performance codecs

A unified architecture for fast and efficient computation of the set of two-dimensional (2-D) transforms adopted by the most recent state-of-the-art digital video standards is presented in this paper. Contrasting to other designs with similar functionality, the presented architecture is supported on a scalable, modular and completely configurable processing structure. This flexible structure not only allows to easily reconfigure the architecture to support different transform kernels, but it also permits its resizing to efficiently support transforms of different orders (e. g. order-4, order-8, order-16 and order-32). Consequently, not only is it highly suitable to realize high-performance multi-standard transform cores, but it also offers highly efficient implementations of specialized processing structures addressing only a reduced subset of transforms that are used by a specific video standard. The experimental results that were obtained by prototyping several configurations of this processing structure in a Xilinx Virtex-7 FPGA show the superior performance and hardware efficiency levels provided by the proposed unified architecture for the implementation of transform cores for the Advanced Video Coding (AVC), Audio Video coding Standard (AVS), VC-1 and High Efficiency Video Coding (HEVC) standards. In addition, such results also demonstrate the ability of this processing structure to realize multi-standard transform cores supporting all the standards mentioned above and that are capable of processing the 8k Ultra High Definition Television (UHDTV) video format (7,680 x 4,320 at 30 fps) in real time.

Layered smart grid architecture approach and field tests by ZigBee technology

This paper presents a layered Smart Grid architecture enhancing security and reliability, having the ability to act in order to maintain and correct infrastructure components without affecting the client service. The architecture presented is based in the core of well design software engineering, standing upon standards developed over the years. The layered Smart Grid offers a base tool to ease new standards and energy policies implementation. The ZigBee technology implementation test methodology for the Smart Grid is presented, and provides field tests using ZigBee technology to control the new Smart Grid architecture approach. (C) 2014 Elsevier Ltd. All rights reserved.

Multifunctional controller architecture for sold-state marx modulator based on FPGA

This paper proposes a multifunctional architecture to implement field-programmable gate array (FPGA) controllers for power converters and presents a prototype for a pulsed power generator based on a solid-state Marx topology. The massively parallel nature of reconfigurable hardware platforms provides very high processing power and fast response times allowing the implementation of many subsystems in the same device. The prototype includes the controller, a failure detection system, an interface with a safety/emergency subsystem, a graphical user interface, and a virtual oscilloscope to visualize the generated pulse waveforms, using a single FPGA. The proposed architecture employs a modular design that can be easily adapted to other power converter topologies.

Characterization and performance analysis of a VDFLL GNSS receiver architecture

A non-coherent vector delay/frequency-locked loop architecture for GNSS receivers is proposed. Two dynamics models are considered: PV (position and velocity) and PVA (position, velocity, and acceleration). In contrast with other vector architectures, the proposed approach does not require the estimation of signals amplitudes. Only coarse estimates of the carrier-to-noise ratios are necessary.

Physical layer aware network architecture for the future internet

In this article, physical layer awareness in access, core, and metro networks is addressed, and a Physical Layer Aware Network Architecture Framework for the Future Internet is presented and discussed, as proposed within the framework of the European ICT Project 4WARD. Current limitations and shortcomings of the Internet architecture are driving research trends at a global scale toward a novel, secure, and flexible architecture. This Future Internet architecture must allow for the co-existence and cooperation of multiple networks on common platforms, through the virtualization of network resources. Possible solutions embrace a full range of technologies, from fiber backbones to wireless access networks. The virtualization of physical networking resources will enhance the possibility of handling different profiles, while providing the impression of mutual isolation. This abstraction strategy implies the use of well elaborated mechanisms in order to deal with channel impairments and requirements, in both wireless (access) and optical (core) environments.