Metodologia de Reconfiguração de Hardware utilizando o Sinal de TV Digital

O presente artigo apresenta um modelo de Set-top Box (STB) com decodificador de vídeo reconfigurável, funcionando a partir do sinal aberto de TV Digital (TVD). O modelo foi baseado em uma plataforma comercial e utiliza um módulo de Field Programmable Gate Array (FPGA) para o processo de reconfiguração, no qual é prevista a atualização do decodificador de vídeo H.264. O sistema efetua a reconfiguração do FPGA a partir de um feixe de bits contendo a descrição de hardware (H.264), o qual é  transmitido juntamente com o conteúdo de TV em alta definição (High Definition Television --  HDTV). Dessa maneira, todos os receptores na área de cobertura da transmissora de TVD podem ser atualizados através de um único sinal. A transmissão e a recepção dos dados de atualização fazem parte do modelo conceitual proposto, cujo desenvolvimento objetiva  a minimização do legado normalmente existente na implantação ou na evolução de um sistema de TVD. Assim, futuras revisões nas normas de TVD poderiam ocorrer sem a necessidade de troca de equipamento

Finding Software Vulnerabilities in Open-Source C Projects via Bounded Model Checking

Computer-based systems have solved several domain problems, including industrial, military, education, and wearable. Nevertheless, such arrangements need high-quality software to guarantee security and safety as both are mandatory for modern software products. We advocate that bounded model-checking techniques can efficiently detect vulnerabilities in general software systems. However, such an approach struggles to scale up and verify extensive code bases. Consequently, we have developed and evaluated a methodology to verify large software systems using a state-of-the-art bounded model checker. In particular, we pre-process input source-code files and guide the respective model checker to explore them systematically. Moreover, the proposed scheme includes a function-wise prioritization strategy, which readily provides results for code entities according to a scale of importance. Experimental results using a real implementation of the proposed methodology show that it can efficiently verify large software systems. Besides, it presented low peak memory allocation when executed. We have evaluated our approach by verifying twelve popular open-source C projects, where we have found real software vulnerabilities that their developers confirmed.Comment: 27 pages, submitted to STTT journa

Diminishing benefits of urban living for children and adolescents’ growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified

Diminishing benefits of urban living for children and adolescents’ growth and development

AbstractOptimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was &lt;1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.</jats:p

Metodologia de Reconfiguração de Hardware utilizando o Sinal de TV Digital

O presente artigo apresenta um modelo de Set-top Box (STB) com decodificador de vídeo reconfigurável, funcionando a partir do sinal aberto de TV Digital (TVD). O modelo foi baseado em uma plataforma comercial e utiliza um módulo de Field Programmable Gate Array (FPGA) para o processo de reconfiguração, no qual é prevista a atualização do decodificador de vídeo H.264. O sistema efetua a reconfiguração do FPGA a partir de um feixe de bits contendo a descrição de hardware (H.264), o qual é  transmitido juntamente com o conteúdo de TV em alta definição (High Definition Television --  HDTV). Dessa maneira, todos os receptores na área de cobertura da transmissora de TVD podem ser atualizados através de um único sinal. A transmissão e a recepção dos dados de atualização fazem parte do modelo conceitual proposto, cujo desenvolvimento objetiva  a minimização do legado normalmente existente na implantação ou na evolução de um sistema de TVD. Assim, futuras revisões nas normas de TVD poderiam ocorrer sem a necessidade de troca de equipamento

Hardware Update through Digital TV Signals

This paper presents a new hardware reconfiguration approach named hardware reconfiguration through digital television (HARD), which can update FPGA hardware modules based on digital TV (DTV) signals. Such a scheme allows several synthesized hardware cores (bitstreams) signaled and broadcast through open DTV signals via data streaming to be identified, acquired, decoded, and then used for system updates. Reconfiguration data are partitioned, encapsulated into private sections, and then sent in a carrousel fashion in order to be recovered by modified receivers. Service information content, specially designed for identifying and describing the characteristics of multiplexed hardware bitstreams, was added to the transmitted signal and provided all necessary information in the traditional DTV style. The receiver framework, in turn, checked whether those characteristics corresponded to its embedded reconfigurable devices and, if a match was found, it reassembled the related bitstreams and reconfigured the respective internal circuits. Experiments performed with an implementation of the proposed methodology confirmed its feasibility and showed that remounting and reconfiguration times were satisfactory and presented no blocking aspect. Finally, HARD can be used in several designs regarding intelligent reconfigurable devices, minimize device costs in the long term, and provide better hardware reuse