RESUMO
The Wi-SUN FAN (Wireless Smart Ubiquitous Network Field Area Network) standard is attracting great interest in various applications such as smart meters, smart cities and Internet of Things (IoT) devices due to the attractive features that the standard offers, such as multihop and mesh topologies, a relatively high data rate, frequency hopping, and interoperability between manufacturers. However, the process of connecting nodes in Wi-SUN FAN networks, which includes discovering, joining, and forming the network, has been shown to be slow, especially in multihop environments, which has motivated research and experimentation to analyze this process. In the existing literature, to measure network formation time, some authors have performed experiments with up to 100 devices, which is a costly and time-consuming methodology. Others have used simulation tools that are difficult to replicate, because little information is available about the methodology used or because they are proprietary. Despite these efforts, there is still a lack of information to adequately assess the formation time of Wi-SUN FAN networks, since the experimental tests reported in the literature are expensive and time-consuming. Therefore, alternatives such as computer simulation have been explored to speed up performance analysis in different scenarios. With this perspective, this paper is focused on the implementation of the Wi-SUN FAN network formation process using the Contiki-NG open source operating system and the Cooja simultor, where a functionality was added that makes it possible to efficiently analyze the network performance, thereby facilitating the implementation of new techniques to reduce network training time. The simulation tool was integrated into Contiki-NG and has been used to estimate the network formation times in various indoor environments. The correspondence between the experimental and numerical results obtained shows that our proposal is efficient to study the formation process of this type of networks.
RESUMO
OBJECTIVE: To investigate the viability of the bispectral index in the sleep evaluation of critically ill patients and to quantify the associations of sleep parameters measured by this index with the Richards-Campbell Sleep Questionnaire and environmental noise. METHODS: This was a cross-sectional observational study that evaluated critically ill adults with diseases of low or moderate severity. The following were measured: total sleep volume and time, deep sleep volume and time, continuous sleep volume and time, sleep onset latency, and environmental sound pressure level. The subjective perception of sleep was evaluated with the Richards-Campbell Sleep Questionnaire the morning after each night of observation. RESULTS: Patients had a low total sleep time (234 minutes), a predominance of superficial sleep stages, and little deep sleep (1.7 minutes). The total, deep, and continuous sleep volumes were 3,679, 9.4, and 3,143 (bispectral index units × minutes), respectively. The sleep latency was 94 minutes. The mean score of the Richards-Campbell Sleep Questionnaire was 57.9. Total sleep volume, total sleep time, and continuous sleep volume were weakly correlated with the Richards-Campbell Sleep Questionnaire depth of sleep domain score, overall sleep quality domain score, and total score. Total volume, total time, and continuous volume were moderately correlated with the occurrence of awakenings domain score. CONCLUSION: The bispectral index is an instrument with limited viability to monitor the sleep of lucid patients and patients with low to moderate disease severity in the intensive care unit. Patients with higher total sleep volume, total sleep time, and continuous sleep volume had better overall sleep perception.
OBJETIVO: Investigar a viabilidade do índice bispectral na avaliação do sono de pacientes criticamente enfermos lúcidos e a associação entre os parâmetros do sono aferidos por esse índice, pelo Questionário de Sono de Richards-Campbell e pelo ruído ambiental. MÉTODOS: Estudo observacional transversal que avaliou indivíduos adultos criticamente enfermos com doenças de gravidades baixa ou moderada. Foram aferidos: volume e tempo total de sono, volume e tempo de sono profundo, volume e tempo de sono contínuo, latência para o início do sono e pressão sonora ambiental. A percepção subjetiva do sono foi registrada com o Questionário de Sono de Richards-Campbell nas manhãs subsequentes às noites de observação. RESULTADOS: Os pacientes apresentaram tempo total de sono reduzido (234 minutos), predominância dos estágios superficiais e pouco sono profundo (1,7 minutos). Os volumes de sono total, profundo e contínuo foram 3.679, 9,4 e 3.143 índice bispectral versus minutos, respectivamente. A latência para o sono foi de 94 minutos. O escore médio do Questionário de Sono de Richards-Campbell foi 57,9. Foram observadas correlações de magnitudes fracas entre volume total, tempo total, volume contínuo e os domínios do Questionário de Sono de Richards-Campbell profundidade do sono, qualidade geral de sono e escore total; e correlações de magnitudes moderadas entre volume total, tempo total, volume contínuo e o domínio ocorrência de despertares. CONCLUSÃO: O índice bispectral é um instrumento com viabilidade limitada para monitorar o sono de pacientes lúcidos e com enfermidades de gravidades baixa e moderada na unidade de terapia intensiva, e pacientes que apresentaram maior volume, tempo total e volume de sono contínuo tiveram melhor percepção global do sono.
Assuntos
Unidades de Terapia Intensiva , Sono , Estado Terminal , Estudos Transversais , Humanos , Inquéritos e QuestionáriosRESUMO
RESUMO Objetivo: Investigar a viabilidade do índice bispectral na avaliação do sono de pacientes criticamente enfermos lúcidos e a associação entre os parâmetros do sono aferidos por esse índice, pelo Questionário de Sono de Richards-Campbell e pelo ruído ambiental. Métodos: Estudo observacional transversal que avaliou indivíduos adultos criticamente enfermos com doenças de gravidades baixa ou moderada. Foram aferidos: volume e tempo total de sono, volume e tempo de sono profundo, volume e tempo de sono contínuo, latência para o início do sono e pressão sonora ambiental. A percepção subjetiva do sono foi registrada com o Questionário de Sono de Richards-Campbell nas manhãs subsequentes às noites de observação. Resultados: Os pacientes apresentaram tempo total de sono reduzido (234 minutos), predominância dos estágios superficiais e pouco sono profundo (1,7 minutos). Os volumes de sono total, profundo e contínuo foram 3.679, 9,4 e 3.143 índice bispectral versus minutos, respectivamente. A latência para o sono foi de 94 minutos. O escore médio do Questionário de Sono de Richards-Campbell foi 57,9. Foram observadas correlações de magnitudes fracas entre volume total, tempo total, volume contínuo e os domínios do Questionário de Sono de Richards-Campbell profundidade do sono, qualidade geral de sono e escore total; e correlações de magnitudes moderadas entre volume total, tempo total, volume contínuo e o domínio ocorrência de despertares. Conclusão: O índice bispectral é um instrumento com viabilidade limitada para monitorar o sono de pacientes lúcidos e com enfermidades de gravidades baixa e moderada na unidade de terapia intensiva, e pacientes que apresentaram maior volume, tempo total e volume de sono contínuo tiveram melhor percepção global do sono.
Abstract Objective: To investigate the viability of the bispectral index in the sleep evaluation of critically ill patients and to quantify the associations of sleep parameters measured by this index with the Richards-Campbell Sleep Questionnaire and environmental noise. Methods: This was a cross-sectional observational study that evaluated critically ill adults with diseases of low or moderate severity. The following were measured: total sleep volume and time, deep sleep volume and time, continuous sleep volume and time, sleep onset latency, and environmental sound pressure level. The subjective perception of sleep was evaluated with the Richards-Campbell Sleep Questionnaire the morning after each night of observation. Results: Patients had a low total sleep time (234 minutes), a predominance of superficial sleep stages, and little deep sleep (1.7 minutes). The total, deep, and continuous sleep volumes were 3,679, 9.4, and 3,143 (bispectral index units × minutes), respectively. The sleep latency was 94 minutes. The mean score of the Richards-Campbell Sleep Questionnaire was 57.9. Total sleep volume, total sleep time, and continuous sleep volume were weakly correlated with the Richards-Campbell Sleep Questionnaire depth of sleep domain score, overall sleep quality domain score, and total score. Total volume, total time, and continuous volume were moderately correlated with the occurrence of awakenings domain score. Conclusion: The bispectral index is an instrument with limited viability to monitor the sleep of lucid patients and patients with low to moderate disease severity in the intensive care unit. Patients with higher total sleep volume, total sleep time, and continuous sleep volume had better overall sleep perception.